| San Marcos to Isabela (Puerto Rico) | 3,245.95 mi (5,223.85 km) |
| San Marcos to Iselin (New Jersey) | 2,400.00 mi (3,862.42 km) |
| San Marcos to Isla Vista (California) | 177.79 mi (286.12 km) |
| San Marcos to Issaquah (Washington) | 1,027.56 mi (1,653.69 km) |
| San Marcos to Ithaca (New York) | 2,288.03 mi (3,682.22 km) |
| San Marcos to Ives Estates (Florida) | 2,265.70 mi (3,646.29 km) |
| San Marcos to Jackson (Michigan) | 1,885.28 mi (3,034.07 km) |
| San Marcos to Jackson (Mississippi) | 1,563.89 mi (2,516.84 km) |
| San Marcos to Jackson (Missouri) | 1,574.40 mi (2,533.74 km) |
| San Marcos to Jackson (Tennessee) | 1,619.43 mi (2,606.22 km) |
| San Marcos to Jackson (Wyoming) | 793.42 mi (1,276.89 km) |
| San Marcos to Jacksonville (Alabama) | 1,804.40 mi (2,903.91 km) |
| San Marcos to Jacksonville (Arkansas) | 1,435.73 mi (2,310.59 km) |
| San Marcos to Jacksonville (Florida) | 2,085.17 mi (3,355.75 km) |
| San Marcos to Jacksonville (Illinois) | 1,558.69 mi (2,508.46 km) |
