The rampart walls were built in several stages and from a variety of materials such as gravel, tuff and sandstone. The lower 15 layers of stone date from before the town’s construction (12th century).
According to original documents in the town’s archives, King Conrad IV requested his citizens to build a 12 foot high wall around the city. In return, King Conrad issued a 4 year tax exemption to all citizens, following the wall’s completion.
A pebbled, herringbone building pattern can be observed in the lower part of the wall.
The wall’s middle section was built from recovered stones about 100 years later. The upper part of the wall was fitted with sandstone blocks, just prior to the Battle of Murten in 1476.