The building was originally built as a loo

The 7ft by 6ft (2m by 1.8m) building, close to Truro's cathedral, has room for a table, chair, computer and very little else.

"It is the smallest office building we have ever sold," estate agent Neil Sargent from Stratton & Holborrow said.

The building, originally built as a loo, is being offered for sale with a 125-year lease at £19,950.

A business is currently being run from the site, which is built over the river on Wilkes Walk.

"There's room for a chair, a table and a computer, but that's it," Mr Sargent said.

"I can stand in it with my arms outstretched and touch the walls.

"When there's two of you in there it gets pretty friendly."