<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <link:roleRef roleURI="http://www.alx-inc.com/role/DocumentAndEntityInformation" xlink:href="alx-20200819.xsd#DocumentAndEntityInformation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/netLabel" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel" xlink:type="simple" />
  <link:presentationLink xlink:role="http://www.alx-inc.com/role/DocumentAndEntityInformation" xlink:type="extended">
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_CoverAbstract" xlink:label="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:type="locator" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_DocumentType" xlink:label="loc_dei_DocumentType_DC183CEFA3805734A92AE3188F11C885" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_DocumentType_DC183CEFA3805734A92AE3188F11C885" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_DocumentPeriodEndDate" xlink:label="loc_dei_DocumentPeriodEndDate_141B5203323F5F699303A43F800457AC" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_DocumentPeriodEndDate_141B5203323F5F699303A43F800457AC" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityRegistrantName" xlink:label="loc_dei_EntityRegistrantName_CAD84F5A298652B19FAF079E782DC99F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_EntityRegistrantName_CAD84F5A298652B19FAF079E782DC99F" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityIncorporationStateCountryCode" xlink:label="loc_dei_EntityIncorporationStateCountryCode_B64A5E45DF4057A3A62F1B3CDCC0A099" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_EntityIncorporationStateCountryCode_B64A5E45DF4057A3A62F1B3CDCC0A099" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityFileNumber" xlink:label="loc_dei_EntityFileNumber_0CA2C54161E358AF95A072C2EB6433F1" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_EntityFileNumber_0CA2C54161E358AF95A072C2EB6433F1" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityTaxIdentificationNumber" xlink:label="loc_dei_EntityTaxIdentificationNumber_8C5474E40C8F5BF99C84C83DB7909AA2" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_EntityTaxIdentificationNumber_8C5474E40C8F5BF99C84C83DB7909AA2" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityAddressAddressLine1" xlink:label="loc_dei_EntityAddressAddressLine1_28393A63D6FB56548BBE475705AA1681" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_EntityAddressAddressLine1_28393A63D6FB56548BBE475705AA1681" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityAddressCityOrTown" xlink:label="loc_dei_EntityAddressCityOrTown_D0B887074CF35F75966BE2DFF4AC12F4" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_EntityAddressCityOrTown_D0B887074CF35F75966BE2DFF4AC12F4" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityAddressStateOrProvince" xlink:label="loc_dei_EntityAddressStateOrProvince_E8AD9C78B06257BE97BD6688A797F29A" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_EntityAddressStateOrProvince_E8AD9C78B06257BE97BD6688A797F29A" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityAddressPostalZipCode" xlink:label="loc_dei_EntityAddressPostalZipCode_6BE83E0EB7A35907863722EB92EF615D" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_EntityAddressPostalZipCode_6BE83E0EB7A35907863722EB92EF615D" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_CityAreaCode" xlink:label="loc_dei_CityAreaCode_527F1DF57BE258549538D89AD5BCFD3C" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_CityAreaCode_527F1DF57BE258549538D89AD5BCFD3C" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_LocalPhoneNumber" xlink:label="loc_dei_LocalPhoneNumber_8F3B44F0DDF95A71A7F94D30E11CA8B6" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_LocalPhoneNumber_8F3B44F0DDF95A71A7F94D30E11CA8B6" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_Security12bTitle" xlink:label="loc_dei_Security12bTitle_EC693F848FE6587A85F07BC242A76E0B" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_Security12bTitle_EC693F848FE6587A85F07BC242A76E0B" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_TradingSymbol" xlink:label="loc_dei_TradingSymbol_8180741832FD5164B30B9D9C5A381B85" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_TradingSymbol_8180741832FD5164B30B9D9C5A381B85" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_SecurityExchangeName" xlink:label="loc_dei_SecurityExchangeName_D0F56D0EA5F7575BA0B15F8BD5A54772" xlink:type="locator" />
    <link:presentationArc order="15" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_SecurityExchangeName_D0F56D0EA5F7575BA0B15F8BD5A54772" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_WrittenCommunications" xlink:label="loc_dei_WrittenCommunications_4E4B05F25BD1595EBB7828FC18E4A454" xlink:type="locator" />
    <link:presentationArc order="16" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_WrittenCommunications_4E4B05F25BD1595EBB7828FC18E4A454" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_SolicitingMaterial" xlink:label="loc_dei_SolicitingMaterial_F2B5E9A6F9F65B568119FBE81E222BFB" xlink:type="locator" />
    <link:presentationArc order="17" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_SolicitingMaterial_F2B5E9A6F9F65B568119FBE81E222BFB" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_PreCommencementTenderOffer" xlink:label="loc_dei_PreCommencementTenderOffer_CDF910CD7BCA5ED3B7CFA4B664586740" xlink:type="locator" />
    <link:presentationArc order="18" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_PreCommencementTenderOffer_CDF910CD7BCA5ED3B7CFA4B664586740" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_PreCommencementIssuerTenderOffer" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_BED0F02115575FE89281425B075754E5" xlink:type="locator" />
    <link:presentationArc order="19" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_BED0F02115575FE89281425B075754E5" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityEmergingGrowthCompany" xlink:label="loc_dei_EntityEmergingGrowthCompany_061AD492832C529CBCAAE1E099F5624F" xlink:type="locator" />
    <link:presentationArc order="20" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_EntityEmergingGrowthCompany_061AD492832C529CBCAAE1E099F5624F" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityCentralIndexKey" xlink:label="loc_dei_EntityCentralIndexKey_DA7156E6A4475F708FC0B7FA1167E46F" xlink:type="locator" />
    <link:presentationArc order="21" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_EntityCentralIndexKey_DA7156E6A4475F708FC0B7FA1167E46F" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_AmendmentFlag" xlink:label="loc_dei_AmendmentFlag_59DD8557F4645DE48A8C7142F9A69336" xlink:type="locator" />
    <link:presentationArc order="22" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_76B6DC67040B5F9C9FC5F5F112E1680D" xlink:to="loc_dei_AmendmentFlag_59DD8557F4645DE48A8C7142F9A69336" xlink:type="arc" />
  </link:presentationLink>
</link:linkbase>
