Lasarte was a long, demanding pre-war road course in the tradition of Nurburgring, Spa, and Brno. Set on undulating, tree-lined public roads, it was the home of Grand Prix racing in Spain from its opening in 1923 until 1935. A dual carriageway has now been built on part of the road from Lasarte to Andoain where the track originally ran between the River Oria and a cliff. The next section to Urnieta and Hernani remains largely unchanged. The anti-clockwise circuit was also known as San Sebastian after the port to the north.