We came as a family with a young child. The place has a baby crib as well as a child chair. It is literally 2 minutes walking to the beach. On the next beach there is also a playground for kids.
city centre is available 10 minutes via bus or 20 minutes walk. So this is amazing place if you want to enjoy Biarritz with a young Kid. Patricia came with her car to the train station to pick us up. which was very kind as we did not have to move from the train station with our suitcases. Great place:)