St. Olav's Church stone church was built before 1150 and probably Telemark's largest stone church in former times. It had a number of unusual building features, including lektorium and a separate room for earthly values, which today is called 'Mary's Chapel'. Probably the church was the main church in Grenland, a kind of 'county church' and therefore had the highest status of all churches in the area. Today the church ruins are located next to the newer Bamble Church.
References:The Broch of Gurness is an Iron Age broch village. Settlement here began sometime between 500 and 200 BC. At the centre of the settlement is a stone tower or broch, which once probably reached a height of around 10 metres. Its interior is divided into sections by upright slabs. The tower features two skins of drystone walls, with stone-floored galleries in between. These are accessed by steps. Stone ledges suggest that there was once an upper storey with a timber floor. The roof would have been thatched, surrounded by a wall walk linked by stairs to the ground floor. The broch features two hearths and a subterranean stone cistern with steps leading down into it. It is thought to have some religious significance, relating to an Iron Age cult of the underground.
The remains of the central tower are up to 3.6 metres high, and the stone walls are up to 4.1 metres thick.