Lunaport was an underground city which was located on Luna, Earth's only natural satellite.
In the 22nd century, the Earth Starfleet operated an EV simulator at Lunaport. The simulator quickly earned the nickname "The Vomitorium". (ENT episode: "The Catwalk")
By the 23rd century, Lunaport was regarded as the United Federation of Planets' fifth largest city and was extensively populated by citizens from all over the Federation. Many citizens were drawn to the city because of its unsurpassed lodging, recreational facilities and transportation systems. (Star Trek reference: The Worlds of the Federation)
In an alternate timeline, Amanda Grayson was killed in a shuttle accident at Lunaport. (TAS episode: "Yesteryear")