Gasklockan, Gothenburg, Industrial heritage site in Gullbergsvass, Gothenburg, Sweden.

Gasklockan was a gasometer at the Gullbergsvass gasworks in Gothenburg, built as a 20-sided polygon with an internal diameter of 44.75 metres and a height of 81 metres to the top. Its outer structure enclosed the gas holder itself, and the gas travelled through pipes with a diameter of 1,000 millimetres. The holder stored 100,000 cubic metres of gas and was delivered by Maschinenfabrik Augsburg-Nürnberg, with Götaverken as subcontractor.

The structure was built in 1933 and stored up to 100,000 cubic meters of gas for Sweden's largest gasworks at Gullbergsvass. After six decades of operation, the facility was decommissioned in 1993 when newer energy sources replaced the gas industry.

The empty gasometer was used for several music videos, including Andreas Johnson's "Glorious" (1999), and for a sound art installation by Åke Parmerud and Olle Niklasson. In 2009 GT readers nominated it among Gothenburg's ugliest buildings, and reporter Jimmy Fredriksson called it one of the Western world's ugliest landmarks.

The site is located in an industrial area and is easily accessible by public transport or car. Visitors should note that the building no longer stands, as it was completely demolished in 2017.

Demolition in 2017 was carried out by lifting the entire structure on 20 jackscrews and removing the lowest section, so the building lost about 2 metres of height per day. The work finished before the 15 March deadline, while the peregrine falcons were still present and had been given nesting boxes at alternative sites.