Grönehög is the biggest ancient mound in Bohuslän region. It has a diameter of 45-50m and it is 6m high. Archaeologists have found buried items from the mound dating from the 6th century AD.References:
Is this possibly where Arrow-Odd was buried? If not, is there an attributable site in Bohuslän for that?
Built around AD 90 to entertain the legionaries stationed at the fort of Caerleon (Isca), the impressive amphitheatre was the Roman equivalent of today’s multiplex cinema. Wooden benches provided seating for up to 6,000 spectators, who would gather to watch bloodthirsty displays featuring gladiatorial combat and exotic wild animals.
Long after the Romans left, the amphitheatre took on a new life in Arthurian legend. Geoffrey of Monmouth, the somewhat imaginative 12th-century scholar, wrote in his History of the Kings of Britain that Arthur was crowned in Caerleon and that the ruined amphitheatre was actually the remains of King Arthur’s Round Table.
Today it is the most complete Roman amphitheatre in Britain.