In 1886, the town was incorporated as the City of Vancouver. It fell victim to the Great Vancouver Fire in the same year, which destroyed all but two of its buildings. The area was completely rebuilt and continued to thrive.

Gastown found new life as the centre of the city's wholesale produce distribution until the Great Depression in the 1930s. After the Depression, Gastown was a largely forgotten neighbourhood of the larger city of Vancouver, and fell into decline and disrepair until the 1960s.

Vancouver's citizens became concerned with preserving Gastown's distinctive and historic architecture. Campaigning resulted in the provincial government declaring Gastown a provincial historical site in 1971, protecting its heritage buildings forever, and the Canadian government designated it a national historic site in 2009.

Gastown's most famous landmark is its steam-powered clock, located on the corner of Cambie and Water Street. The clock was built to cover a steam grate that was part of Vancouver's distributed steam-heating system. The clock was built as a way to harness the steam and to prevent street people from sleeping on the spot in cold weather.

A plant adjacent to the Georgia Viaduct generates the low-pressure steam that powers a miniature steam engine in the base of the clock, which drives a chain lift that moves steel balls upward, where they are unloaded and roll to a descending chain. The weight of the balls on the descending chain drives a conventional pendulum clock escapement, geared to the hands on the four faces. The steam also powers the clock's sound production, which uses whistles to to signal the time and produce the Westminster chime. Each 1/4 hour the clock sounds the chimes on 5 brass steam whistlers.