Helsinki's Senate Square is surrounded by Neoclassical architecture. It is dominated by four buildings designed by Carl Ludvig Engel between 1822 and 1852. These are Helsinki Cathedral, the National Library of Finland, the Government Palace and the University of Helsinki.

Helsinki Cathedral, which recently celebrated its 150th anniversary, is probably Finland's most photographed building. Sederholm House, located on the southeast corner of the Square, is the oldest stone building in Helsinki.