Round Rock is 20 miles (32 km) north of Austin and is most easily reached by car via I-35. The drive from Austin city centre takes about 25 minutes in normal traffic, though rush hours on I-35 can double that.
The Capital Metro commuter rail line (the MetroRail) connects downtown Austin to the Lakeline station on the southern edge of Round Rock, but does not run into the city centre itself. From Lakeline, local buses connect to various parts of Round Rock. For most visitors arriving from out of state, Austin-Bergstrom International Airport (AUS) is the practical gateway, about 35 miles (55 km) south; car rental is the most convenient option from there.