Klaragasverket, Industrial gas plant in central Stockholm, Sweden.

Klaragasverket was a coal-based gas production plant located beside Klara Lake in central Stockholm. Its red brick buildings were decorated with brown and yellow brick patterns, forming a compact industrial complex on the waterfront.

The plant was founded in 1853 as Stockholm's first gas facility, supplying the city with gas for street lighting and household use. It was decommissioned in 1919 when other energy sources became more widely available.

The plant brought gas lighting to Stockholm's streets, which changed the way people moved through the city after dark. For many residents, it marked the beginning of a more modern way of life in the home and in public spaces.

The site of the plant is now occupied by the World Trade Center in central Stockholm, near Klara sjö. The original buildings no longer stand, so there is nothing of the gasworks itself to see. The location can be reached on foot from the central station area and is close to the waterfront.

The site chosen for the plant was a former city rubbish tip on Klara sjö, described in the sources as land built up over years from refuse and waste, which flooded at high water and formed a foul-smelling swamp. Piling and gravel fill were needed before construction could start in 1852.