The rock that gives Round Rock its name is still right there in Brushy Creek, a large rounded limestone boulder that has sat in the streambed for millennia. It sits within Chisholm Trail Crossing Park, a pleasant riverside green space on the northwest edge of the old downtown.
It is a genuinely modest sight — a rock in a creek — but the historical significance is real. The Chisholm Trail's Round Rock crossing was one of the major crossing points on the entire trail, and the town grew up around the commerce the drives generated. Standing here, watching the water flow past, it is easy to imagine the noise and dust of a herd of several thousand longhorns picking their way through.