Baltimore

 was an American city, situated in the state of Maryland, proximate to both Bethesda and Washington, DC. (PDA: Blue Box)

It was Peri Brown's home town and the location of a Cyberman invasion in September 1984 which was thwarted by the Sixth Doctor. (BFA: The Reaping)

It was also Edgar Allan Poe's home town. The First Doctor, Ian Chesterton and Barbara Wright once encountered Poe there, near the end of his life. (ST: The True and Indisputable Facts in the Matter of the Ram's Skull)

The Institute of Space Studies, a research organisation which UNIT consulted on extraterrestrial phenomena, was headquartered there. (DW: Spearhead from Space)

Some of its known inhabitants, aside from Peri, were her mother Janine Foster, her late father Paul Brown, Anthony, Kathy and Nate Chambers, Daniel Woods, Lt. Doyle, Mrs van Gysegham and Natalie Hamilton. (BFA: The Reaping)

The city was in ruins for many years after the 22nd century Dalek invasion. (BFA: Nekromanteia)