Oslo's architecture is very diverse. The architect Carl Frederik Stanley (1769–1805), who was educated in Copenhagen, spent some years in Norway around the turn of the 19th century. He did minor works for wealthy patrons in and around Oslo, but his major achievement was the renovation of the Oslo Katedralskole, completed in 1800. He added a classical portico to the front of an older structure, and a semicircular auditorium that was sequestered by Parliament in 1814 as a temporary place to assemble, now preserved at Norsk Folkemuseum as a national monument.