| SeaTac to Cividale del Friuli | 5,441.60 mi (8,757.41 km) |
| SeaTac to Civita Castellana | 5,647.17 mi (9,088.25 km) |
| SeaTac to Civitanova Marche | 5,618.56 mi (9,042.21 km) |
| SeaTac to Civitavecchia | 5,643.75 mi (9,082.74 km) |
| SeaTac to Civitella in Val di Chiana | 5,562.47 mi (8,951.93 km) |
| SeaTac to Clusone | 5,371.50 mi (8,644.60 km) |
| SeaTac to Coccaglio | 5,391.19 mi (8,676.29 km) |
| SeaTac to Codigoro | 5,487.04 mi (8,830.53 km) |
| SeaTac to Codogno | 5,408.32 mi (8,703.86 km) |
| SeaTac to Codroipo | 5,439.39 mi (8,753.85 km) |
| SeaTac to Cogoleto | 5,427.03 mi (8,733.95 km) |
| SeaTac to Colle di Val d'Elsa | 5,548.96 mi (8,930.18 km) |
| SeaTac to Colle Salvetti | 5,520.67 mi (8,884.66 km) |
| SeaTac to Collecchio | 5,445.46 mi (8,763.62 km) |
| SeaTac to Colleferro | 5,696.26 mi (9,167.25 km) |
