If you are at the back of the passport control queue it can take up to 40 minutes to get through. When you get off the plane try and get ahead of as many people as possible. There will be lots of families coming to stay in the area.
More specific info (in French) about the strike affecting Biarritz airport:
On fait le point pour l'aéroport de Biarritz-Pays Basque suite contrôleurs déclarés gréviste au 23-04-24 18h00 LT :
Services ATS du contrôle aérien LFBZ : Fermé de 06h30 à 14h30 LT
Services ATS du contrôle aérien...
Uber has only just started in the region and it widely hated by taxis and private hire drivers (VTC) alike.
You can also book a direct private airport transfer with someone like: https://biarritzairporttransfers.com/destination/saint-jean-pied-de-port/
I just checked the company out, they are a genuine company run by a local from Saint Jean Pied de Port. He can be trusted and provides as good a service as Express Bourricot.
I've been watching with interest the river levels here: https://www.vigicrues.gouv.fr/niv3-station.php?CdEntVigiCru=32&CdStationHydro=Q935251001&GrdSerie=H&ZoomInitial=3
And webcams of the rivers here: https://www.bayonne.fr/ma-mairie/webcams
Quickest way is a direct airport taxi/transfer and the journey takes about 1 hour 30 minutes. Alternatively get the bus to San Sebastián then change for another bus to Biarritz.
Express Bourricot finish at 18:00 so you could book a private transfer with Biarritz Airport Transfers. If your flight lands on time you can be leaving the airport within 15 minutes (don't know if you are flying national or international). Then the journey is 55 minutes to 1 hour.
You could also book a direct airport transfer from Bilbao to Saint Jean Pied de Port. It'll be expensive but you can be in Saint Jean Pied de Port the same night.
You can get the TxikTxak bus number 3 or 4 directly from the airport bus station. After you leave the luggage collection area, turn left and walk to the far end of the airport building. Leave via the sliding doors and there is a covered walkway to the bus station.
You can get a train from Bayonne to Hendaye then walk across the car park and get a Euskotren to Irun.
Or from Bayonne the number 3 bus goes as far as Hendaye.
Something fell on one of the tracks yesterday so it caused huge delays. News from the local paper (only in French): https://www.sudouest.fr/economie/transports/circulation-en-gironde/sncf-la-circulation-des-trains-tres-fortement-perturbee-ce-samedi-dans-le-sud-ouest-16312906.php
I would get the SNCF train from Biarritz to Hendaye then, depending on where you are staying in Irun, you can walk across the border to Irun or get the Euskotren to whichever stop is closest to your accommodation.
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