Dover House is a mansion on Whitehall in Westminster that later became the Scotland Office. It is a database landmark rather than a mission location.
Prince Frederick, Duke of York, added its portico and round hall, then swapped it with Lord Melbourne in 1792. It took the Dover name after George Agar-Ellis became Baron Dover in 1831, and in 1885 it became the Scotland Office.
Dover House sits on Whitehall among the government buildings of Westminster, near Horse Guards and Downing Street.
10 Downing Street
10 Downing Street is the Prime Minister's home and office in Westminster. In 1868 Benjamin Disraeli lives here, and Jacob's work as his bodyguard in Sequence 7 starts outside the house.
Admiralty
The Admiralty is a government office on Whitehall in Westminster, one of the period buildings you can climb and read about in the in-game database. No memory centres on it.
Banqueting Hall
The Banqueting Hall, later the Chapel Royal, is a 1622 hall on Whitehall in Westminster and a database landmark in Syndicate. It is the only surviving part of the old Palace of Whitehall.
Blue Anchor Alley
Blue Anchor Alley is a Blighter stronghold in Westminster run under Lilla Graves, one of two in that borough. Freeing it lets the Rooks set up there instead.