The Starfleet War Memorial was built by the Earth Starfleet in San Francisco, California after the Xindi attack on the planet Earth in the year 2153.
History and specifics[]
The memorial was originally intended to commemorate the lives lost in the Xindi crisis, but after the commencement of the war with the Romulan Star Empire, Starfleet expanded the memorial's purpose to include all of those lost in the Romulan War and beyond. (ENT novel: Last Full Measure)