Tokyo Base

From Memory Alpha, the free Star Trek reference

Tokyo Base is a facility in Japan, on Earth, set up for military command operations. In the 2350s, tactical adviser Kyle Riker worked out the Fuurinkazan battle strategies here. (TNG: "The Icarus Factor")

This base was probably located in or near Tokyo. Its not clear whether it was a Starfleet facility, or if it was operated by the Earth government or another Federation agency.