The Royal Cornwall Museum on River Street is the county's main museum and, by some distance, the best. It covers Cornish natural history, archaeology, and art across a handsome early 19th-century building with surprisingly good depth of content.
The highlight is the mineral collection — tens of thousands of specimens from Cornwall's mining past, representing every geological era the county has passed through. The archaeology galleries cover the Cornish Bronze Age, Iron Age, and Roman period in detail, with finds from local sites. The art collection includes works by local painters, some of them Newlyn School artists from the late 19th century. Entry is paid but modest.