San Sebastián to Biarritz distance

San Sebastián to Biarritz by road

The fastest driving route is 49.1 km (30.5 mi) long and takes about 40 min without stops or traffic. It runs mostly on the A63 (21.7 km), the AP-1 (12.5 km), and the GI-20 (5.8 km).

Of the 49.1 km, 19.0 km are in Spain and 30.1 km are in France. That’s an average of 74 km/h (46 mph), and at under two hours you can do it without stopping. The time is OSRM’s estimate with OpenStreetMap data: no traffic and speeds somewhat below the limits, so real trips can differ.

Straight-line distance and bearing

In a straight line, the shortest distance over the Earth’s surface, San Sebastián and Biarritz are 39.0 km (24.2 mi) apart. That’s the geodesic on the WGS84 ellipsoid, the distance “as the crow flies”.

The road is 26% longer: for every 100 km in a straight line you drive 126. That’s a normal detour between two cities. Of the 34 Spain–Europe driving pairs in this series, it ranks 18th for detour (the average is 31%).

From San Sebastián, Biarritz lies to the northeast (bearing 63°), and from Biarritz, San Sebastián lies to the southwest.

Halfway between San Sebastián and Biarritz

Halfway along the straight line, 19.5 km (12.1 mi) from each city, is the point 43.4013° N, 1.7715° W. It falls in the water; the closest place is Hondarribia (Gipuzkoa, pop. 16,788), 4.6 km away. The nearest town of 20,000 people or more is Irun (Gipuzkoa, pop. 63,835), 7.2 km away.

By road, the halfway point is 24.5 km (15.2 mi) from each city, near Urrugne (Pyrénées-Atlantiques, France, pop. 7,580), 2.2 km away. The nearest town of 20,000 people or more is Irun (Gipuzkoa, pop. 63,835), 5.7 km away. The two midpoints almost coincide (7.2 km apart), because the road doesn’t stray far from the straight line.

Time zone

San Sebastián and Biarritz share the same time all year: both are on Central European Time.

The two cities

San Sebastián has 189,866 people (INE population register, January 1, 2025) and Biarritz 33,188 people (GeoNames).