<SUBMISSION>
<ACCESSION-NUMBER>0001020569-04-000020
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>2
<PERIOD>20040507
<FILING-DATE>20040510
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>LITTLE ARTHUR D
<CIK>0001183339
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-13045
<FILM-NUMBER>04793586
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>745 ATLANTIC AVE
<CITY>BOSTON
<STATE>MA
<ZIP>02111
<PHONE>6175354932
</BUSINESS-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>IRON MOUNTAIN INC/PA
<CIK>0001020569
<ASSIGNED-SIC>4220
<IRS-NUMBER>232588479
<STATE-OF-INCORPORATION>PA
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>745 ATLANTIC AVENUE
<CITY>BOSTON
<STATE>MA
<ZIP>02111
<PHONE>6175354766
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>745 ATLANTIC AVENUE
<CITY>BOSTON
<STATE>MA
<ZIP>02111
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>PIERCE LEAHY CORP
<DATE-CHANGED>19960807
</FORMER-COMPANY>
</ISSUER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-05-07</periodOfReport>

    <issuer>
        <issuerCik>0001020569</issuerCik>
        <issuerName>IRON MOUNTAIN INC/PA</issuerName>
        <issuerTradingSymbol>IRM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001183339</rptOwnerCik>
            <rptOwnerName>LITTLE ARTHUR D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>P.O. BOX 166</rptOwnerStreet1>
            <rptOwnerStreet2>HUNTRESS BRIDGE ROAD</rptOwnerStreet2>
            <rptOwnerCity>S. EFFINGHAM</rptOwnerCity>
            <rptOwnerState>NH</rptOwnerState>
            <rptOwnerZipCode>03882</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, parvalue $.01 per</value>
            </securityTitle>
            <transactionDate>
                <value>2004-05-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4131</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>24.2083</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4131</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, parvalue $.01 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2004-05-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4131</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>44.68</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>24.2083</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-05-07</value>
                <footnoteId id="F2"/>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4131</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>24.2083</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2003-06-01</value>
            </exerciseDate>
            <expirationDate>
                <value>2010-06-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4131</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The full per share exercise price of this grant is $24.2083333</footnote>
        <footnote id="F2">As of the date of the filing, Mr. Little holds no direct ownership of Iron Mountain Common Stock and holds 45,000 shares indirectly. The indirectly held shares are held by Mr. Little as beneficiary of the Little Family Trust.</footnote>
        <footnote id="F3">Mr. Little has excercised 4,131 shares of the non-qualified stock option granted to him on 6/1/00. There are no remaining shares on this stock option.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Clare A. Dever, under Power of Attorney dated November 14, 2002 from Arthur D. Little</signatureName>
        <signatureDate>2004-05-10</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>attach_1.htm
<TEXT>
<HTML><BODY><PRE>POWER OF ATTORNEY



KNOW ALL MEN BY THESE PRESENTS, that I,  Arthur D. Little, residing at P.O. Box 166 Huntress Bridge Road, S. Effingham, NH 03882, do hereby make, constitute and appoint, Garry B. Watzke or Clare A. Dever, being, respectively, the General Counsel and Director of Special Legal Services of Iron Mountain Incorporated, acting singly, to be my lawful attorney-in-fact for me and to do any and all acts which I could do in connection with any filings required by Section 16 of the Securities Exchange Act of 1934, including, without limitation, the preparation, signing and filing of Forms 3, 4 and 5 ("Section 16 Filings").



Among the powers granted to my attorney-in-fact are:



To prepare, sign and file with the Securities and Exchange Commission and the New York Stock Exchange the Section 16 Filings, in my name or stead, and any and all such further documents as he/she may deem necessary or advisable in order to carry out the required Section 16 Filings and the powers granted to him/her by these presents.



This Power of Attorney shall remain in effect until revoked by the undersigned in writing.



IN WITNESS WHEREOF, I have hereunto set my hand and seal this 14th day of November, 2002.







________________________________________



Name:    /s/          Arthur D. Little



STATE OF         Massachussetts             )

                                            )  ss.

COUNTY OF     Suffolk                       )



Then personally appeared, before me, the aforesaid Arthur D. Little, who to me, acknowledged that the foregoing was his free act and deed,



Before me,





  /s/   Garry B. Watzke

 Notary Public



My Commission Expires:  05/29/2009







</PRE></BODY></HTML>

</TEXT>
</DOCUMENT>
</SUBMISSION>
