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                                                                       EXHIBIT 3
                    CERTIFICATE OF DESIGNATION, PREFERENCES
                         AND RIGHTS OF SERIES A JUNIOR
                         PARTICIPATING PREFERRED STOCK

                                       of

                           AMERICAN TELECASTING, INC.


             Pursuant to Section 151 of the General Corporation Law
                            of the State of Delaware


                  The undersigned officer of American Telecasting, Inc., a
corporation organized and existing under the General Corporation Law of the
State of Delaware (the "Corporation"), in accordance with the provisions of
Section 103 thereof, DOES HEREBY CERTIFY:

                  That pursuant to the authority conferred upon the Board of
Directors by the Restated Certificate of Incorporation, as amended, of the
Corporation (the "Restated Certificate of Incorporation"), the Board of
Directors of the Corporation on April 29, 1999 adopted the following resolution
creating a series of 300,000 shares of Preferred Stock designated as Series A
Junior Participating Preferred Stock:

                  RESOLVED, that pursuant to the authority vested in the Board
of Directors of this Corporation in accordance with the provisions of its
Restated Certificate of Incorporation, a series of Preferred Stock of the
Corporation be and it hereby is created, and that the designation and amount
thereof and the voting powers, preferences and relative, participating,
optional and other special rights of the shares of such series, and the
qualifications, limitations or restrictions thereof are as follows:

                  Section I. Designation and Amount. The shares of such series
shall be designated as "Series A Junior Participating Preferred Stock" and the
number of shares constituting such series shall be 300,000.



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                  Section II.  Dividends and Distributions.

                  A. Subject to the prior and superior rights of the holders of
any shares of any series of Preferred Stock ranking prior and superior to the
shares of Series A Junior Participating Preferred Stock with respect to
dividends, if any, the holders of shares of Series A Junior Participating
Preferred Stock shall be entitled to receive, when, as and if declared by the
Board of Directors out of funds legally available for the purpose, quarterly
dividends payable in cash on the last day of March, June, September and
December in each year (each such date being referred to herein as a "Quarterly
Dividend Payment Date"), commencing on the first Quarterly Dividend Payment
Date after the first issuance of a share or fraction of a share of Series A
Junior Participating Preferred Stock, in an amount per share (rounded to the
nearest cent) equal to the greater of (a) $1.00 or (b) subject to the provision
for adjustment hereinafter set forth, 100 times the aggregate per share amount
of all cash dividends, and 100 times the aggregate per share amount (payable in
kind) of all non-cash dividends or other distributions other than a dividend
payable in shares of Class A Common Stock, par value $0.01 per share, of the
Corporation ( the "Common Stock") or a subdivision of the outstanding shares of
Common Stock (by reclassification or otherwise), declared on the Common Stock
since the immediately preceding Quarterly Dividend Payment Date, or, with
respect to the first Quarterly Dividend Payment Date, since the first issuance
of any share or fraction of a share of Series A Junior Participating Preferred
Stock. In the event the Corporation shall at any time after April 29, 1999 (the
"Rights Declaration Date") (i) declare any dividend on Common Stock payable in
shares of Common Stock, (ii) subdivide the outstanding Common Stock, or (iii)
combine the outstanding Common Stock into a smaller number of shares, then in
each such case the amount to which holders of shares of Series A Junior
Participating Preferred Stock were entitled immediately prior to such event
under clause (b) of the preceding sentence shall be adjusted by multiplying
such amount by a fraction the numerator of which is the number of shares of
Common Stock outstanding immediately after such event and the denominator of
which is the number of shares of Common Stock that were outstanding immediately
prior to such event.

                  B. The Corporation shall declare a dividend or distribution
on the Series A Junior Participating Preferred Stock as provided in Paragraph
(A) above immediately after it declares a dividend or distribution on the
Common Stock (other than a dividend payable in shares of Common Stock);
provided that, in the event no dividend or distribution shall have been
declared on the Common Stock during the period between any Quarterly Dividend
Payment Date and the next subsequent 




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Quarterly Dividend Payment Date, a dividend of $0.01 per share on the Series A
Junior Participating Preferred Stock shall nevertheless be payable on such
subsequent Quarterly Dividend Payment Date.

                  C. Dividends shall begin to accrue and be cumulative on
outstanding shares of Series A Junior Participating Preferred Stock from the
Quarterly Dividend Payment Date next preceding the date of issue of such shares
of Series A Junior Participating Preferred Stock, unless the date of issue of
such shares is prior to the record date for the first Quarterly Dividend
Payment Date, in which case dividends on such shares shall begin to accrue from
the date of issue of such shares, or unless the date of issue is a Quarterly
Dividend Payment Date or is a date after the record date for the determination
of holders of shares of Series A Junior Participating Preferred Stock entitled
to receive a quarterly dividend and before such Quarterly Dividend Payment
Date, in either of which events such dividends shall begin to accrue and be
cumulative from such Quarterly Dividend Payment Date. Accrued but unpaid
dividends shall not bear interest. Dividends paid on the shares of Series A
Junior Participating Preferred Stock in an amount less than the total amount of
such dividends at the time accrued and payable on such shares shall be
allocated pro rata on a share-by-share basis among all such shares at the time
outstanding. The Board of Directors may fix a record date for the determination
of holders of shares of Series A Junior Participating Preferred Stock entitled
to receive payment of a dividend or distribution declared thereon, which record
date shall be no more than 30 days prior to the date fixed for the payment
thereof.

                  Section III. Voting Rights. The holders of shares of Series A
Junior Participating Preferred Stock shall have the following voting rights:

                  A. Subject to the provision for adjustment hereinafter set
forth, each share of Series A Junior Participating Preferred Stock shall
entitle the holder thereof to 100 votes on all matters submitted to a vote of
the stockholders of the Corporation. In the event the Corporation shall at any
time after the Rights Declaration Date (i) declare any dividend on Common Stock
payable in shares of Common Stock, (ii) subdivide the outstanding Common Stock,
or (iii) combine the outstanding Common Stock into a smaller number of shares,
then in each such case the number of votes per share to which holders of shares
of Series A Junior Participating Preferred Stock were entitled immediately
prior to such event shall be adjusted by multiplying such number by a fraction
the numerator of which is the number of shares of Common Stock outstanding
immediately after such event and the denominator of which is the 




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number of shares of Common Stock that were outstanding immediately prior to
such event.

                  B. Except as otherwise provided herein or by law, the holders
of shares of Series A Junior Participating Preferred Stock and the holders of
shares of Common Stock shall vote together as one class on all matters
submitted to a vote of stockholders of the Corporation.

                  C. 1. If at any time dividends on any Series A Junior
Participating Preferred Stock shall be in arrears in an amount equal to six (6)
quarterly dividends thereon, the occurrence of such contingency shall mark the
beginning of a period (herein called a "default period") which shall extend
until such time when all accrued and unpaid dividends for all previous
quarterly dividend periods and for the current quarterly dividend period on all
shares of Series A Junior Participating Preferred Stock then outstanding shall
have been declared and paid or set apart for payment. During each default
period, all holders of Preferred Stock (including holders of the Series A
Junior Participating Preferred Stock) with dividends in arrears in an amount
equal to six (6) quarterly dividends thereon, voting as a class, irrespective
of series, shall have the right to elect two (2) directors.

                     2. During any default period, such voting right of
         the holders of Series A Junior Participating Preferred Stock may 
         be exercised initially at a special meeting called pursuant to
         subparagraph (iii) of this Section 3(C) or at any annual meeting of
         stockholders, and thereafter at annual meetings of stockholders,
         provided that neither such voting right nor the right of the holders
         of any other series of Preferred Stock, if any, to increase, in
         certain cases, the number of directors, shall be exercised unless the
         holders of ten percent (10%) in number of shares of Preferred Stock
         outstanding shall be present in person or by proxy. The absence of a
         quorum of the holders of Common Stock shall not affect the exercise by
         the holders of Preferred Stock of such voting right. At any meeting at
         which the holders of Preferred Stock shall exercise such voting right
         initially during an existing default period, they shall have the
         right, voting as a class, to elect directors to fill such vacancies,
         if any, in the Board of Directors as may then exist up to two (2)
         directors or, if such right is exercised at an annual meeting, to
         elect two (2) directors. If the number which may be so elected at any
         special meeting does not amount to the required number, the holders of
         the Preferred Stock shall have the right to make such increase in the
         number of directors as shall be necessary to permit the election by
         them of the required number. After the holders of the Preferred Stock
         shall have exercised their 




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         right to elect directors in any default period and during the
         continuance of such period, the number of directors shall not be
         increased or decreased except by vote of the holders of Preferred
         Stock as herein provided or pursuant to the rights of any equity
         securities ranking senior to or pari passu with the Series A Junior
         Participating Preferred Stock.

                           3. Unless the holders of Preferred Stock shall,
         during an existing default period, have previously exercised their
         right to elect directors, the Board of Directors may order, or any
         stockholder or stockholders owning in the aggregate not less than ten
         percent (10%) of the total number of shares of Preferred Stock
         outstanding, irrespective of series, may request, the calling of a
         special meeting of the holders of Preferred Stock, which meeting shall
         thereupon be called by the President, a Vice-President or the
         Secretary of the Corporation. Notice of such meeting and of any annual
         meeting at which holders of Preferred Stock are entitled to vote
         pursuant to this Paragraph (C)(iii) shall be given to each holder of
         record of Preferred Stock by mailing a copy of such notice to him or
         her at his or her last address as the same appears on the books of the
         Corporation. Such meeting shall be called for a time not earlier than
         20 days and not later than 60 days after such order or request or in
         default of the calling of such meeting within 60 days after such order
         or request, such meeting may be called on similar notice by any
         stockholder or stockholders owning in the aggregate not less than ten
         percent (10%) of the total number of shares of Preferred Stock
         outstanding. Notwithstanding the provisions of this Paragraph
         (C)(iii), no such special meeting shall be called during the period
         within 60 days immediately preceding the date fixed for the next
         annual meeting of the stockholders.

                           4. In any default period, the holders of Common
         Stock, and other classes of stock of the Corporation if applicable,
         shall continue to be entitled to elect the whole number of directors
         until the holders of Preferred Stock shall have exercised their right
         to elect two (2) directors voting as a class, after the exercise of
         which right (x) the directors so elected by the holders of Preferred
         Stock shall continue in office until their successors shall have been
         elected by such holders or until the expiration of the default period,
         and (y) any vacancy in the Board of Directors may (except as provided
         in Paragraph (C)(ii) of this Section 3) be filled by vote of a
         majority of the remaining directors theretofore elected by the holders
         of the class 




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         of stock which elected the director whose office shall have become
         vacant. References in this Paragraph (C) to directors elected by the
         holders of a particular class of stock shall include directors elected
         by such directors to fill vacancies as provided in clause (y) of the
         foregoing sentence.

                           5. Immediately upon the expiration of a default
         period, (x) the right of the holders of Preferred Stock as a class to
         elect directors shall cease, (y) the term of any directors elected by
         the holders of Preferred Stock as a class shall terminate, and (z) the
         number of directors shall be such number as may be provided for in the
         Restated Certificate of Incorporation or bylaws of the Corporation
         irrespective of any increase made pursuant to the provisions of
         Paragraph (C)(ii) of this Section 3 (such number being subject,
         however, to change thereafter in any manner provided by law or in the
         Restated Certificate of Incorporation or bylaws of the Corporation).
         Any vacancies in the Board of Directors effected by the provisions of
         clauses (y) and (z) in the preceding sentence may be filled by a
         majority of the remaining directors.

                  D. Except as set forth herein, holders of Series A Junior
Participating Preferred Stock shall have no special voting rights and their
consent shall not be required (except to the extent they are entitled to vote
with holders of Common Stock as set forth herein) for taking any corporate
action.

                  Section IV.  Certain Restrictions.

                  A. Whenever quarterly dividends or other dividends or
distributions payable on the Series A Junior Participating Preferred Stock as
provided in Section 2 are in arrears, thereafter and until all accrued and
unpaid dividends and distributions, whether or not declared, on shares of
Series A Junior Participating Preferred Stock outstanding shall have been paid
in full, the Corporation shall not:

                                    1.  declare or pay dividends on, make any 
         other distributions on, or redeem or purchase or otherwise acquire for
         consideration any shares of stock ranking junior (either as to
         dividends or upon liquidation, dissolution or winding up) to the
         Series A Junior Participating Preferred Stock;

                                    2.  declare or pay dividends on or make any
         other distributions on any shares of stock ranking on a parity (either
         as 




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         to dividends or upon liquidation, dissolution or winding up) with the
         Series A Junior Participating Preferred Stock, except dividends paid
         ratably on the Series A Junior Participating Preferred Stock and all
         such parity stock on which dividends are payable or in arrears in
         proportion to the total amounts to which the holders of all such
         shares are then entitled;

                                    3. redeem or purchase or otherwise acquire
         for consideration shares of any stock ranking on a parity (either as
         to dividends or upon liquidation, dissolution or winding up) with the
         Series A Junior Participating Preferred Stock, provided that the
         Corporation may at any time redeem, purchase or otherwise acquire
         shares of any such parity stock in exchange for shares of any stock of
         the Corporation ranking junior (either as to dividends or upon
         dissolution, liquidation or winding up) to the Series A Junior
         Participating Preferred Stock; or

                                    4. purchase or otherwise acquire for
         consideration any shares of Series A Junior Participating Preferred
         Stock, or any shares of stock ranking on a parity with the Series A
         Junior Participating Preferred Stock, except in accordance with a
         purchase offer made in writing or by publication (as determined by the
         Board of Directors) to all holders of such shares upon such terms as
         the Board of Directors, after consideration of the respective annual
         dividend rates and other relative rights and preferences of the
         respective series and classes, shall determine in good faith will
         result in fair and equitable treatment among the respective series or
         classes.

                  B. The Corporation shall not permit any subsidiary of the
Corporation to purchase or otherwise acquire for consideration any shares of
stock of the Corporation unless the Corporation could, under Paragraph (A) of
this Section 4, purchase or otherwise acquire such shares at such time and in
such manner.

                  Section V. Reacquired Shares. Any shares of Series A Junior
Participating Preferred Stock purchased or otherwise acquired by the
Corporation in any manner whatsoever shall be retired and cancelled promptly
after the acquisition thereof. All such shares shall upon their cancellation
become authorized but unissued shares of Preferred Stock and may be reissued as
part of a new series of Preferred Stock to be created by resolution or
resolutions of the Board of Directors, subject to the conditions and
restrictions on issuance set forth herein.



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                  Section VI. Liquidation, Dissolution or Winding Up. A. Upon
any liquidation (voluntary or otherwise), dissolution or winding up of the
Corporation, no distribution shall be made to the holders of shares of stock
ranking junior (either as to dividends or upon liquidation, dissolution or
winding up) to the Series A Junior Participating Preferred Stock unless, prior
thereto, the holders of shares of Series A Junior Participating Preferred Stock
shall have received an amount equal to $100 per share of Series A Participating
Preferred Stock, plus an amount equal to accrued and unpaid dividends and
distributions thereon, whether or not declared, to the date of such payment
(the "Series A Liquidation Preference"). Following the payment of the full
amount of the Series A Liquidation Preference, no additional distributions
shall be made to the holders of shares of Series A Junior Participating
Preferred Stock unless, prior thereto, the holders of shares of Common Stock
shall have received an amount per share (the "Common Adjustment") equal to the
quotient obtained by dividing (i) the Series A Liquidation Preference by (ii)
100 (as appropriately adjusted as set forth in subparagraph (C) below to
reflect such events as stock splits, stock dividends and recapitalizations with
respect to the Common Stock) (such number in clause (ii), the "Adjustment
Number"). Following the payment of the full amount of the Series A Liquidation
Preference and the Common Adjustment in respect of all outstanding shares of
Series A Junior Participating Preferred Stock and Common Stock, respectively,
holders of Series A Junior Participating Preferred Stock and holders of shares
of Common Stock shall receive their ratable and proportionate share of the
remaining assets to be distributed in the ratio of the Adjustment Number to 1
with respect to such Preferred Stock and Common Stock, on a per share basis,
respectively.

                  B. In the event, however, that there are not sufficient
assets available to permit payment in full of the Series A Liquidation
Preference and the liquidation preferences of all other series of preferred
stock, if any, which rank on a parity with the Series A Junior Participating
Preferred Stock, then such remaining assets shall be distributed ratably to the
holders of such parity shares in proportion to their respective liquidation
preferences. In the event, however, that there are not sufficient assets
available to permit payment in full of the Common Adjustment, then such
remaining assets shall be distributed ratably to the holders of Common Stock.

                  C. In the event the Corporation shall at any time after the
Rights Declaration Date (i) declare any dividend on Common Stock payable in
shares of Common Stock, (ii) subdivide the outstanding Common Stock, or (iii)
combine the outstanding Common Stock into a smaller number of shares, then in
each such case the Adjustment Number in effect immediately prior to such event
shall be adjusted by multiplying such Adjustment Number by a fraction the
numerator of which is the number of shares of Common Stock outstanding
immediately after such event and 





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the denominator of which is the number of shares of Common Stock that were
outstanding immediately prior to such event.

                  Section VII. Consolidation, Merger, etc. In case the
Corporation shall enter into any consolidation, merger, combination or other
transaction in which the shares of Common Stock are exchanged for or changed
into other stock or securities, cash and/or any other property, then in any
such case the shares of Series A Junior Participating Preferred Stock shall at
the same time be similarly exchanged or changed in an amount per share (subject
to the provision for adjustment hereinafter set forth) equal to 100 times the
aggregate amount of stock, securities, cash and/or any other property (payable
in kind), as the case may be, into which or for which each share of Common
Stock is changed or exchanged. In the event the Corporation shall at any time
after the Rights Declaration Date (i) declare any dividend on Common Stock
payable in shares of Common Stock, (ii) subdivide the outstanding Common Stock,
or (iii) combine the outstanding Common Stock into a smaller number of shares,
then in each such case the amount set forth in the preceding sentence with
respect to the exchange or change of shares of Series A Junior Participating
Preferred Stock shall be adjusted by multiplying such amount by a fraction the
numerator of which is the number of shares of Common Stock outstanding
immediately after such event and the denominator of which is the number of
shares of Common Stock that were outstanding immediately prior to such event.

                  Section VIII. No Redemption. The shares of Series A Junior
Participating Preferred Stock shall not be redeemable.

                  Section IX. Amendment. At any time when any shares of Series
A Junior Participating Preferred Stock are outstanding, the Restated
Certificate of Incorporation of the Corporation shall not be further amended in
any manner which would materially alter or change the powers, preferences or
special rights of the Series A Junior Participating Preferred Stock so as to
affect them adversely without the affirmative vote of the holders of a majority
or more of the outstanding shares of Series A Junior Participating Preferred
Stock, voting separately as a class.

                  Section X. Fractional Shares. Series A Junior Participating
Preferred Stock may be issued in fractions of a share which shall entitle the
holder, in proportion to such holders fractional shares, to exercise voting
rights, receive dividends, participate in distributions and to have the benefit
of all other rights of holders of Series A Junior Participating Preferred
Stock.




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                  IN WITNESS WHEREOF, we have executed and subscribed this
Certificate and do affirm the foregoing as true under the penalties of perjury
this 7th day of May, 1999.


                                        AMERICAN TELECASTING, INC.


                                        By:  /s/ David K. Sentman          
                                           ------------------------------------
                                        Name:  David K. Sentman
                                        Title:  Senior Vice President and Chief
                                                Financial Officer





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