Tycho City

Tycho City is located on Earth's Moon and probably part of the Lunar colonies. The city has self-contained atmosphere and artificial gravity (presumably to Earth standard).

By 2373, it was large enough to be seen from Earth at daytime, since Commander William Riker missed the familiar sight of the city, while looking at the Moon during his mission to the year 2063. 

The city lies on the shores of Lake Armstrong, opposite the city of New Berlin. (: A Stranger No More)

Cadet Dorian Collins was from Tycho City. Brothers Ben and Jason Bartholomew were also from Tycho, and their parents kept a home there until the 2380s. (PDN: "L'Morte d'Maquis", A Stranger No More, et. al)

Pulsar Gamma Corporation had offices in Tycho City. (PDN: A Stranger No More})

The Tycho City Titans were a popular Parrises squares team in the late 24th century, rivals of the neighboring New Berlin Barons. (PDN: "More to This Life")

Background
A nod to the film 2001: A Space Odyssey, Tycho City was first mentioned by Will Riker in Star Trek: First Contact. It was referenced again several times in Deep Space Nine, and has become a popular background location in many fan fiction stories.