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  <xs:element id="alx_TerrorismCoverageIncludingNbcrMember" abstract="true" name="TerrorismCoverageIncludingNbcrMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_NbcrMember" abstract="true" name="NbcrMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_FiftyNinthStreetInsuranceCompanyLlcMember" abstract="true" name="FiftyNinthStreetInsuranceCompanyLlcMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_InsuranceMaximumCoveragePerProperty" abstract="false" name="InsuranceMaximumCoveragePerProperty" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_InsuranceMaximumCoveragePerIncident" abstract="false" name="InsuranceMaximumCoveragePerIncident" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_InsuranceMaximumCoverageInAggregate" abstract="false" name="InsuranceMaximumCoverageInAggregate" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_InsuranceDeductible" abstract="false" name="InsuranceDeductible" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_SelfInsuredResponsibility" abstract="false" name="SelfInsuredResponsibility" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_FederalGovernmentResponsibility" abstract="false" name="FederalGovernmentResponsibility" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_GainsLossesOnSalesOfInvestmentRealEstateIncludingDiscontinuedOperations" abstract="false" name="GainsLossesOnSalesOfInvestmentRealEstateIncludingDiscontinuedOperations" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_RealEstateAndAccumulatedDepreciationCarryingAmountOfDevelopmentAndConstructionInProgress" abstract="false" name="RealEstateAndAccumulatedDepreciationCarryingAmountOfDevelopmentAndConstructionInProgress" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_RealEstateAndAccumulatedDepreciationYearOfConstruction" abstract="false" name="RealEstateAndAccumulatedDepreciationYearOfConstruction" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:gYearItemType"/>
  <xs:element id="alx_RealEstateAndAccumulatedDepreciationYearAcquired" abstract="false" name="RealEstateAndAccumulatedDepreciationYearAcquired" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:gYearItemType"/>
  <xs:element id="alx_SECSchedule1228RealEstateCompaniesInvestmentInRealEstateRealEstateBeforeRealEstateSoldAndWrittenOff" abstract="false" name="SECSchedule1228RealEstateCompaniesInvestmentInRealEstateRealEstateBeforeRealEstateSoldAndWrittenOff" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_SECSchedule1228RealEstateCompaniesInvestmentInRealEstateAccumulatedDepreciationWriteOffOfAssets" abstract="false" name="SECSchedule1228RealEstateCompaniesInvestmentInRealEstateAccumulatedDepreciationWriteOffOfAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
