The Senate Square and its surroundings form a unique and cohesive example of Neoclassical architecture. The square is dominated by four buildings designed by Carl Ludvig Engel (1778-1840): Helsinki Cathedral, the Government Palace, the main building of the University of Helsinki and the National Library of Finland. A statue of Alexander II (1894) stands in the middle of the Senate Square. Helsinki Cathedral is arguably Finland's most famous and photographed building; it celebrates its 165th anniversary in 2017. The oldest stone building in Helsinki is the Sederholm House located on the southeast corner of the square. Today the building hosts the Helsinki City Museum. The Esplanade park and the Market Square are just a block away.
The Senate Square also hosts a sound installation called the Sound of the Senate Square. It is a modern version of the European glockenspiel and can be heard every day at 17:49 as it travels from one building to the next. The composition runs for 5 minutes 18 seconds and is composed by Harri Viitanen and Jyrki Alakuijala.