Originally, Round Rock was not named Round Rock nor was it located where it is currently. Coincidence and fate combined to determine the location of Round Rock. The initial settlement of Brushy (as the town was originally called) was located near the banks of Brushy Creek at the natural fording area by the round rock. This settlement grew and flourished despite a succession of floods.

Then in 1876, with the coming of the International and Great Northern Railroad, most businesses realized that commercial activity would shift to the new location along the tracks and prepared to abandon Old Town for the New Town location. After the opening of the rail line in 1876, the two Round Rocks functioned and were both shown on maps and official documents as Old Round Rock and New Round Rock. At times, New Town was referred to as merely Round Rock; On December 16, 1891, the post office at Old Town was closed down, by this time most of Old Town had been abandoned. Interest in Old Town waned until the middle of the twentieth century when individuals began to take an interest in the fine old stone buildings and restoration work began. At this time, the street through Old Town was renamed Chisholm Trail in order to call attention to the historical nature of the area.