Kong Humbles Grav ("King Humble's Grave") is one of Langelands most well-known prehistoric dolmens. It is about 55m long and 9m wide. Around the sides of the long barrow there are set of 74-77 kerb stones. The archaeological excavation has revealed c. 4000 years old human bones in the grave. The grave name is misleading, because the King "Humble" is believed to lived in c. 300-400 AD.
References:Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.