You can take all types of transport. However if you want to catch the last train to St JPdeP at 18:20, take a taxi from the airport to the SNCF station in Bayonne. It will cost you around 12 euros.
I took a taxi from the airport to SJPP this past May. I think it was worth the 75 Euro expense. I had a bike. Email me and I will give you the name of the great driver/owner who picked me up.
depends what time you land in biaritz. if you arrive before 5 , i would take the bus, that way you can take the last train. ST.pdp is well worth staying at least 1/2 day,
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