According to Adam of Bremen and the "Saxo Grammaticus", Roskilde was founded in the 980s by Harald Bluetooth. On high ground above the harbour, he built a wooden church consecrated to the Holy Trinity as well as a royal residence nearby. Although no traces of these buildings have been discovered, in 1997 archaeologists found the remains of Viking ships in the Isefjord, the oldest of which is dated to 1030. At the time, there were also two churches in the area: St Jørgensbjerg, an early stone church, and a wooden church discovered under today's St Ib's Church. Harald was buried in the wooden church he had built on the site of today's Roskilde Cathedral.