The calculated distance (air line) between Garachico and San Sebastián de la Gomera is approximately 29 miles respectively 46 kilometers.
By car or train, the actual journey to San Sebastián de la Gomera is certainly longer, as only the direct route (as the crow flies) between Garachico and San Sebastián de la Gomera has been calculated here.
Air line (approximately)
46 kilometers
25 nautical miles