Complex sentence: Archaeologists familiar with the area have concluded this is the site of Joara and Fort San Juan and evidence of the documented Spanish settlement of 1566-1568, as well as the natives' burning of the fort.
Split into simpler sentences: Archaeologists familiar with the area have concluded this is the site of Joara and Fort San Juan. It supports documented Spanish settlement of 1567-1568, as well as the natives' burning of the fort.