Buckingham Palace.

Buckingham Palace has served as the official London residence of the British monarchy since 1837. While most visitors congregate outside the gates for the Changing of the Guard—a choreographed display of military precision—the interior is seasonally accessible. During the summer months, the public can tour the nineteen State Rooms, which function as the setting for official ceremonial duties. These spaces are essentially a living gallery, housing Sèvres porcelain and masterworks from the Royal Collection amidst lavish English and French furniture. The experience extends to the 39-acre garden, a curated "walled oasis" featuring a lake and several hundred varieties of wildflowers. For a more complete look at royal life, the adjacent Royal Mews houses the monarch’s historic carriages, while the Queen’s Gallery hosts rotating art exhibitions.