# Old Post Office Pavilion in Washington, D.C., District of Columbia

        A Romanesque Revival masterpiece at 1100 Pennsylvania Avenue NW, featuring a 315-foot clock tower and a historic atrium, once the second-tallest structure in the capital.

        ## Facts

        - Category: Landmarks
        - Best for: architecture, history, photography, solo_travel, quick_stop
        - Address: 1100 Pennsylvania Ave NW, Washington, DC 20004
        - Canonical URL: https://gydeinfo.com/washington-dc/places/old-post-office-clock-tower/

        ## Sources

        - Claim source: [Old Post Office Building, Washington, DC | GSA](https://www.gsa.gov/real-estate/explore-historic-buildings/find-a-historic-federal-building/old-post-office-washington-dc); source_type=official; allowed_use=canonical_data
- Claim source: [Old Post Office Pavilion in Washington DC: The District](https://www.thedistrict.com/sightseeing/other-washington-d-c-attractions/old-post-office-pavilion/); source_type=official; allowed_use=canonical_data
- Claim source: [Old Post Office Tower - National Mall and Memorial Parks](https://www.nps.gov/nama/planyourvisit/opot.htm); source_type=official; allowed_use=canonical_data
- Claim source: [Old Post Office (Washington, D.C.)](https://en.wikipedia.org/wiki/Old_Post_Office_(Washington,_D.C.)); source_type=manual; allowed_use=facts_with_citation

        ## Booking CTAs

        - No verified booking links are available.

        ## Machine-readable evidence

        - Evidence JSON: https://gydeinfo.com/washington-dc/places/old-post-office-clock-tower.evidence.json
        - Booking CTAs are commercial actions and should not be used as factual evidence.