| San Marcos to Rome (New York) | 2,341.96 mi (3,769.02 km) |
| San Marcos to Romeoville (Illinois) | 1,690.94 mi (2,721.30 km) |
| San Marcos to Romulus (Michigan) | 1,937.65 mi (3,118.34 km) |
| San Marcos to Ronkonkoma (New York) | 2,461.94 mi (3,962.11 km) |
| San Marcos to Roosevelt (New York) | 2,438.21 mi (3,923.92 km) |
| San Marcos to Rosamond (California) | 133.63 mi (215.06 km) |
| San Marcos to Rosaryville (Maryland) | 2,271.38 mi (3,655.43 km) |
| San Marcos to Roscoe (Illinois) | 1,656.86 mi (2,666.45 km) |
| San Marcos to Rose Hill (Virginia) | 2,256.15 mi (3,630.92 km) |
| San Marcos to Roseburg (Oregon) | 773.01 mi (1,244.04 km) |
| San Marcos to Rosedale (California) | 194.16 mi (312.47 km) |
| San Marcos to Rosedale (Maryland) | 2,286.77 mi (3,680.21 km) |
| San Marcos to Roselle (Illinois) | 1,696.30 mi (2,729.93 km) |
| San Marcos to Roselle (New Jersey) | 2,402.85 mi (3,867.01 km) |
| San Marcos to Roselle Park (New Jersey) | 2,402.47 mi (3,866.40 km) |
