This mighty church ruin from the early Middle Ages holds many secrets. The construction of St. Olof's Church most probably began during the first half of the 12th century. The remains of it have been the subject of several smaller scientific excavations during the 2000s, when researchers have been curious about the church's strange architecture. Through the excavations, it has been found that the church we see remains of today rests on an older building - perhaps the oldest stone church in Sweden. St. Olof's plan is strange, the choir is both larger and longer than the nave. The idea was certainly to build a longhouse as grand as the choir, but for some reason it didn't happen. The construction stopped, perhaps due to lack of money. There was probably a wooden longhouse throughout the Middle Ages. Next to the south wall of the church today is the foundation for a small house with a dried out well. The small house was built earlier than the church and may have been built over a sacred spring, an Olof spring.

Source: https://destinationsigtuna.se/