<SUBMISSION>
<ACCESSION-NUMBER>0001020569-04-000051
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>19880808
<FILING-DATE>20040831
<DATE-OF-FILING-DATE-CHANGE>20040831
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>MILLER ROBERT G
<CIK>0001183340
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-13045
<FILM-NUMBER>041009071
</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>
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    <documentType>4</documentType>

    <periodOfReport>1988-08-08</periodOfReport>

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

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            <rptOwnerName>MILLER ROBERT G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>IRON MOUNTAIN INFORMATION MGMT, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>1000 CAMPUS DRIVE</rptOwnerStreet2>
            <rptOwnerCity>COLLEGEVILLE</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19426</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Pres. Iron Mountain's Records</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

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        </nonDerivativeHolding>
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        <derivativeTransaction>
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            </conversionOrExercisePrice>
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            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
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                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F10"/>
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            <exerciseDate>
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            <expirationDate>
                <value>2010-04-23</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
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                </underlyingSecurityTitle>
                <underlyingSecurityShares>
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                    <footnoteId id="F6"/>
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                </sharesOwnedFollowingTransaction>
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        <derivativeTransaction>
            <securityTitle>
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            <conversionOrExercisePrice>
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            </conversionOrExercisePrice>
            <transactionDate>
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                <transactionCode>J</transactionCode>
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            <expirationDate>
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            <underlyingSecurity>
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                <underlyingSecurityShares>
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                    <footnoteId id="F7"/>
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                    <value>D</value>
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                    <value></value>
                </natureOfOwnership>
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        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>25.60</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-06-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>3906</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F10"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F8"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-03-26</value>
            </expirationDate>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>11718</value>
                    <footnoteId id="F8"/>
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                    <value>D</value>
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        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (Right to Buy)</value>
            </securityTitle>
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                <value>25.60</value>
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                <value>2004-06-15</value>
            </transactionDate>
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                <transactionFormType>5</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>2605</value>
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                <transactionPricePerShare>
                    <footnoteId id="F10"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F9"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-03-26</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>7814</value>
                    <footnoteId id="F9"/>
                </underlyingSecurityShares>
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                <sharesOwnedFollowingTransaction>
                    <value>7814</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Common Stock of Iron Mountain Incorporated split 3-for-2 to all record holders as of June 15, 2004, resulting in reporting person's acquisition of 18,248 shares of Common Stock.</footnote>
        <footnote id="F2">This stock option was previously reported as covering 10,409 shares at an exercise price of $2.8817778 per share, but adjusted to reflect a 3-for-2 stock split effective June 30, 2004. All shares are vested.</footnote>
        <footnote id="F3">This stock option was previously reported as covering 12,470 shares at an exercise price of $22.4166667 per share, but adjusted to reflect a 3-for-2 stock split effective June 30, 2004. The 13,687 shares are vested and                                the 5,018 remainder shares will vest on 9/13/04.</footnote>
        <footnote id="F4">This stock option was previously reported as covering 4,256 shares at an exercise price of $22.4166667 per share, but adjusted to reflect a 3-for-2 stock split effective June 30, 2004. All shares are vested.</footnote>
        <footnote id="F5">This stock option was previously reported as covering 7,769 shares at an exercise price of $22.5208333 per share, but adjusted to reflect a 3-for-2 stock split effective June 30, 2004. The 4,993 shares are vested                        and the 6,661 remainder shares will vest on 4/24/05.</footnote>
        <footnote id="F6">This stock option was previously reported as covering 27,754 shares at an exercise price of $22.5208333 per share, but adjusted to reflect a 3-for-2 stock split effective June 30, 2004. The 37,632 shares are vested                             and the 3,999 remainder shares will vest on 4/24/05.</footnote>
        <footnote id="F7">This stock option was previously reported as covering 22,472 shares at an exercise price of $22.25 per share, but adjusted to reflect a 3-for-2 stock split effective June 30, 2004. The 20,224 are vested and the remainder                           shares will vest as follows: 6,741 shares on 11/15/04 and 6,743 shares on 11/15/05.</footnote>
        <footnote id="F8">This stock option was previously reported as covering 7,812 shares at an exercise price of $38.40 per share, but adjusted to reflect a 3-for-2 stock split effective June 30, 2004. Of these 11,718 shares, no shares are                           vested. 3,906 shares shall vest annually on each of the following dates: 3/27/06, 3/27/07 and 3/27/08.</footnote>
        <footnote id="F9">This stock option was previously reported as covering 5,209 shares at an exercise price of $38.40 per share, but adjusted to reflect a 3-for-2 stock split effective June 30, 2004. The 3,906 shares are vested and the                            remainder shares will vest as follows: 3,906 shares on 3/27/05 and 2 shares on 3/28/08.</footnote>
        <footnote id="F10">Note: This report is being voluntarily filed at this time to report the effect of the above referenced 3-for-2 stock split. Therefore, there is no price to be reported. In addition, the fictitious date of &quot;08/08/1988&quot; has been                       used in the &quot;Date of Earliest Transaction&quot; field 3, prior to Table I. Since there is no transaction required to be reported and this field requires that data be inserted, a fictitious date has been used.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Robert G. Miller</signatureName>
        <signatureDate>2004-08-25</signatureDate>
    </ownerSignature>
</ownershipDocument>

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</SUBMISSION>
