Riksgropen, Archaeological excavation in Gamla stan, Stockholm, Sweden.

Riksgropen was the popular name for the excavation pit that opened in 1978 on Riksplan, the square in front of the Riksdag building on Helgeandsholmen. The dig, led by Anders Ödman and Marietta Douglas, ran until autumn 1981 and exposed 13th-century house foundations, remains of the early 16th-century city wall, eleven boats and about 1,300 skeletons from the Helgeandshuset cemetery.

The excavation began in the 1970s and 1980s when archaeologists uncovered 13th-century ruins and early modern fortifications while preparing the site for a parking garage. These discoveries changed the plans for the land and led to the creation of a medieval museum instead.

The site shows how people lived, worked, and buried their dead across many centuries in this same location. You can see how the city built itself up layer by layer as different generations used the same ground.

Riksgropen no longer exists as an open pit: it was dug from spring 1978 to autumn 1981 and then built over. The finds are displayed in the Stockholm Medieval Museum, entered from Norrbro on Helgeandsholmen. The museum closed on 5 November 2023 after the Riksdag terminated its lease from the end of 2024, so check access before visiting.

The excavation also uncovered eleven boats from four different centuries, buried in the silt of Helgeandsholmen, and the remains of the Morianen pharmacy from the 1600s. Coins, glass bottles, medieval ceramics and clay pipes came out of the same trenches. The digs were led by Anders Ödman and Marietta Douglas and ran from spring 1978 to autumn 1981.