San Miguel can be found on the Salinas River of northern San Luis Obispo County. San Miguel is home to 1797 Mission San Miguel Arcangel which was a way point on the Spanish El Camino Real. US 101 was plotted over Legislative Route 2 in late 1926 which put the original alignment on Mission Street through San Miguel. Mission Street was bypassed when the current freeway alignment of US 101 opened in 1957.
https://www.gribblenation.org/2021/01/former-us-route-101-in-san-miguel.html?m=1
I've always been intrigued by the southern Mission Street interchange in San Miguel, mostly because, up until a few years ago, the southbound onramp merged onto US 101 from the left (via the median), not the right. I always figured that configuration was due to the adjacent frontage road on the west side of the freeway. If the ramp had been built to merge on the right, the frontage road would have to move farther west, which may have not been possible due to the cemetery just southwest of the interchange.
Thankfully, Caltrans has added a southbound US 101 underpass so that the southbound onramp now merges on the right.