<SEC-DOCUMENT>0001051470-20-000023.txt : 20200221
<SEC-HEADER>0001051470-20-000023.hdr.sgml : 20200221
<ACCEPTANCE-DATETIME>20200221181953
ACCESSION NUMBER:		0001051470-20-000023
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200219
FILED AS OF DATE:		20200221
DATE AS OF CHANGE:		20200221

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Kelley Philip M
		CENTRAL INDEX KEY:			0001442369

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-16441
		FILM NUMBER:		20641494

	MAIL ADDRESS:	
		STREET 1:		1220 AUGUSTA DRIVE SUITE 500
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77057

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CROWN CASTLE INTERNATIONAL CORP
		CENTRAL INDEX KEY:			0001051470
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				760470458
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1220 AUGUSTA DRIVE
		STREET 2:		SUITE 600
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77057
		BUSINESS PHONE:		7135703000

	MAIL ADDRESS:	
		STREET 1:		1220 AUGUSTA DRIVE
		STREET 2:		SUITE 600
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77057
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_158232717611804.xml
<DESCRIPTION>FORM 4
<TEXT>
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    <periodOfReport>2020-02-19</periodOfReport>

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        <issuerName>CROWN CASTLE INTERNATIONAL CORP</issuerName>
        <issuerTradingSymbol>CCI</issuerTradingSymbol>
    </issuer>

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            <rptOwnerName>Kelley Philip M</rptOwnerName>
        </reportingOwnerId>
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            <rptOwnerStreet1>1220 AUGUSTA DR</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 600</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77057</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior VP, Corp Dev &amp; Strategy</officerTitle>
            <otherText></otherText>
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                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by 401(K) Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
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    <derivativeTable>
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                </underlyingSecurityTitle>
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                <transactionPricePerShare>
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    <footnotes>
        <footnote id="F1">Represents shares withheld by the issurer to satisfy the Reporting Person's tax withholding obligation in connection with the vesting of certain Restricted Stock Units (&quot;RSUs&quot;) previously granted to the Reporting Person. Such withholding is exempt from Section 16(b) pursuant to Rule 16b-3(e).</footnote>
        <footnote id="F2">Represents shares previously acquired in transactions exempt under Rule 16b-3(c).</footnote>
        <footnote id="F3">Each Restricted Stock Unit (&quot;RSU&quot;) is issued pursuant to the Company's 2013 Long-Term Incentive Plan and represents a contingent right to receive one share of common stock and vesting (i.e., forfeiture restriction termination) generally is subject to (i) the reporting person remaining an employee or director of the Company or its affiliates and (ii) the other criteria described in the footnotes below.</footnote>
        <footnote id="F4">20,104 Performance RSUs vested on February 19, 2020, based upon the Company's total stockholder return performance ranking relative to a peer group of companies approved by the Company's board of directors for the three year period ended February 16, 2020. The remainder of the original Performance RSUs granted in February 2017 did not vest on February 19, 2020 and were forfeited</footnote>
        <footnote id="F5">These Time RSUs were previously granted on February 16, 2017. 33 1/3% of the original grant amount of these Time RSUs vested on February 19 of each of 2018, 2019 and 2020.</footnote>
        <footnote id="F6">These Time RSUs were previously granted on February 21, 2018. 33 1/3% of the original grant amount of these Time RSUs vest on February 19 of each of 2019, 2020 and 2021.</footnote>
        <footnote id="F7">These Time RSUs were previously granted on February 21, 2019. 33 1/3% of the original grant amount of these Time RSUs vest on February 19 of each of 2020, 2021 and 2022.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Philip M. Kelley</signatureName>
        <signatureDate>2020-02-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
