Rim Drive of Crater Lake National Park is a 33 mile loop around the volcanic caldera of the namesake lake. The earliest iteration of Rim Drive (Rim Road) was completed by 1918 and the current facility was completed by 1941. Modern Rim Drive is presently listed on the National Register of Historic Places. The blog below contains the history of the development of Rim Road and it's evolution into modern Rim Drive. The blog also explores the development of the Jacksonville-Fort Klamath Stage Road into Oregon Route 62/Crater Lake Highway, Oregon Route 209 at the North Entrance Road and what was Oregon Route 232 via the long abandoned East Entrance Road.
https://www.gribblenation.org/2021/09/rim-drive-and-roads-of-crater-lake.html