There are about 150 runic inscriptions in the area, most dating from the early 11th century and located beside ancient roads. Sigtuna has many quaint streets and wooden buildings still following the medieval town plan but, apart from the church, the original buildings didn't survive the devastating late-medieval town fires. The ruins of the churches of Saint Per, Saint Olaf and Saint Lars remain. Mariakyrkan , the oldest brick building in the area, has restored medieval paintings. In summer, many people head for the coast and the islands or organise picnics in the parks .
Tourist offices can supply maps of cycle routes.
Sweden's most important chieftain in the mid-13th century, Birger Jarl, ordered the construction of a fort on one of the strategically placed islets where the fresh water entered the sea, and traffic on the waterways was controlled using timber stocks arranged as a fence, or boom. Stockholm, meaning 'tree-trunk islet,' may well be named after this boom. The oldest record of the city consists of two letters dating from 1252. During the period of the Kalmar Union, the king's governor directed affairs from the castle. The city was periodically ravaged by fire until timber buildings with turf roofs were replaced with brick structures.