The oldest part of the present school is the Harsdorff building (Munkegata 8), which was completed in 1786.

The building is named after its designer Caspar Harsdorff, a royal Danish architect.

Festival Hall on the second floor has two marble reliefs by noted Danish sculptor Bertel Thorvaldsen (1770–1844).

In 1920, the school underwent a major expansion, with buildings designed by Norwegian architect Carl J. Moe (1889–1942).

The school has a separate dance and music program, offers Latin courses and the IB Diploma course for local students who want to travel abroad or for international students who move to the city.