<SEC-DOCUMENT>0001051470-21-000061.txt : 20210222
<SEC-HEADER>0001051470-21-000061.hdr.sgml : 20210222
<ACCEPTANCE-DATETIME>20210222173612
ACCESSION NUMBER:		0001051470-21-000061
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210218
FILED AS OF DATE:		20210222
DATE AS OF CHANGE:		20210222

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Ackerman Robert Carl
		CENTRAL INDEX KEY:			0001716196

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-16441
		FILM NUMBER:		21661739

	MAIL ADDRESS:	
		STREET 1:		1220 AUGUSTA DRIVE SUITE 600
		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_161403334334921.xml
<DESCRIPTION>FORM 4
<TEXT>
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    <documentType>4</documentType>

    <periodOfReport>2021-02-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001051470</issuerCik>
        <issuerName>CROWN CASTLE INTERNATIONAL CORP</issuerName>
        <issuerTradingSymbol>CCI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001716196</rptOwnerCik>
            <rptOwnerName>Ackerman Robert Carl</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1220 AUGUSTA DRIVE SUITE 600</rptOwnerStreet1>
            <rptOwnerStreet2></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>EVP-COO-Towers</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

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                <value>Time RSUs</value>
            </securityTitle>
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            <transactionDate>
                <value>2021-02-18</value>
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                <transactionFormType>4</transactionFormType>
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                    <value>6579</value>
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                <transactionPricePerShare>
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                <transactionPricePerShare>
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                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>10220</value>
                </transactionShares>
                <transactionPricePerShare>
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                <sharesOwnedFollowingTransaction>
                    <value>10220</value>
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    <footnotes>
        <footnote id="F1">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="F2">33 1/3% of the Time RSUs vest on February 19 of each of 2022, 2023 and 2024.</footnote>
        <footnote id="F3">0% to 150% of these Relative TSR Performance RSUs may vest on February 19, 2024 based on the Company's annualized total stockholder return (&quot;TSR&quot;) performance ranking (&quot;TSR Rank&quot;) relative to the constituent companies of the Standard &amp; Poor's 500 Index for the three-year period ending December 31, 2023. The percentage of Relative TSR Performance RSUs that may vest will be (a) 0% if the TSR Rank is below the 30th percentile; (b) 50% if the TSR Rank is at the 30th percentile; (c) 100% if the TSR Rank is at the 55th percentile; and (d) 150% if the TSR Rank is at the 90th percentile or greater. If the TSR Rank is between the 30th and 55th percentiles or between the 55th and 90th percentiles, the percentage of Relative TSR Performance RSUs that may vest is determined using linear interpolation.</footnote>
        <footnote id="F4">0% to 150% of these Absolute TSR Performance RSUs may vest on February 19, 2024 based on the Company's annualized TSR for the three-year period ending December 31, 2023. The percentage of Absolute TSR Performance RSUs that may vest will be (a) 0% if TSR is below 6.5%; (b) 50% if TSR is 6.5%; (c) 100% if TSR is 11.5%; and (d) 150% if TSR is 16.5% or greater. If TSR is between 6.5% and 11.5% or between 11.5% and 16.5%, the percentage of Absolute TSR Performance RSUs that may vest is determined using linear interpolation.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Robert Carl Ackerman</signatureName>
        <signatureDate>2021-02-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
