Old Aker Church
The church was built over the former site of the Akerberg mines ("Akersberg gruve"), an ancient silver mine which was in use since the early Viking era. The mines are mentioned in the 1170 "Historia Norvegiae". The existence of these former mines must have been the inspiration for a number of local stories about the church having hidden silver treasures and even dungeons with dragons.
Old Aker Cemetery () is the cemetery of Old Aker Church. Like the church, the cemetery dates back to the Middle Ages. The cemetery is located adjacent to the newer Cemetery of Our Saviour, which was established in 1808. Several notable people are interred in the cemetery.
Oslo City Hall
The idea of building a new city hall in Pipervia was first suggested by Oscar Hoff (an architect) in 1906, but nothing came of the plans. In 1915, the idea was taken up by Hieronymus Heyerdahl, who had just stood down as mayor. He noticed the city's lack of a representative city hall to receive the municipality's guests during the 1914 Jubilee Exhibition in Frogner. He set up an architectural competition which received a total of 44 entries in the first of two rounds. In 1918 Arnstein Arneberg and Magnus Poulsson were selected as winners, whose project was clearly inspired by Stockholm City Hall. A continuned lack of funds meant that construction had to wait, and in the intervening years the architects made several changes to the project. In 1930 they present their final draft, which had undergone significant changes, influenced by functionalism. The most apparent change was the addition of two office towers.