Location: US-87 and US-277, San Angelo Exit for US-277 south. Loop 378 also terminates here, but there is no way to access it from US-87 south. 378 traffic comes in, but does not leave. S to TX-306 Loop/TX-FM1223, N to TX-RM584 N to TX-RM584, S to TX-RM584 E to US-87/TX-FM1223, W to TX-RM584 N to … Continue reading U.S. Route 87, TX-306 Loop to US-277/TX-378 Loop