RM 620

The 27.1-mile road, opened in 1945, begins at SH 71 in Bee Cave (Travis County), passes along southeastern Lake Travis, western Austin, and several suburban communities before ending at I-35 in Round Rock (Williamson County). along the way RM 620 intersects US 183, Toll 183 and Toll 45 (running parallel for some miles). Today the road is officially designated as Urban Road 620, although the Ranch to Market signage remains.