Very spacious apartment in a traditional Basque building in a prime location. It's a lovely old building so if you're after hotel-style bathrooms etc, this place may not be for you. But if you like character and quirkiness, you're in luck.
Easy walking distance to three main beaches, centre ville, and very near Les Halles (the market) and nearby bars and restaurants. Also close to bus stops to the airport and other local towns. The buses are cheap and efficient. We went up to Bayonne - beautiful city on two rivers with very interesting museum of Basque culture - and Bidart - very pretty village where we sat out in the village square drinking cider watching the locals doing Basque dancing to a live band.
Jens, who manages the apartment, is very laid back. He was there to meet us as planned, let us stay beyond 11am and leave our bags in the apartment until we left for the airport.
All in all a great base for exploring Biarritz and beyond.