Does anyone have information on reasonably priced tours round trip between Bilbao and the Altamira National Museum and Research Center? Public transportation takes 4 hours each way according to Rome2Rio and the only tours that I can find are private tours hovering around $1000. A car rental is out of the question.

Sorry, I don't have info about that. But if you haven't already done so, you might send a personal message to mikelg. You probably know that he's based in Bilbao.

I would contact your hotel in Bilbao and inquire.

That could possibly work if I were staying at a hotel. I'f meeting a relative who is renting an apartment. But Mikelg has told me that I probably will not find a reasonable solution. I have found an alternative. Our daughter and spouse are in the process of buying a house in Gijon which is the same distance from Altamira as Bilbao. So when we'll visit Gijon ...

If mikelg didn't think you had a reasonable solution, I doubt there was one to be had! I'm glad you identified an option -- the Altamira Caves are fascinating, as are a number of other caves with prehistoric art in that part of Spain.

The original Altamira caves, as I assume mikelg has told you, have been closed to the public for many years. I was one of the last few to be able to see them on an art history trip with my Profesor, Enrique Lafuente Ferrari and even have a photograph from inside the caves! (allowing photography. heaven forbid is one of the reasons they were closed for good).

The replica in the Altamira Museum isn't really a replica, like Lascaux, as mikelg always notes, but instead more of a museum. It and the town of Santillana Del Mar can be seen in a couple of hours.

I remember that kja has visited several original ones still open to the public (remember from that wonderful trip report!) and we have really enjoyed El Castillo and Las Monedas in Puente Viesgo. Our visit was in Spanish. Read all about the visitable Cantabrian caves here.

OMG, Maribel -- how I envy you!

I was so glad to have seen those caves!
Thanks for remembering my trip report and speaking of it so kindly.

Yes, Iīve indicated that itīs more a museum than a real replica. There are plenty of other options in the area with real caves and real cave paintings...not as espectacular as (the real) Altamira, but well worth the visit. All of them need previous reservation and the itīs a guided visit in Spanish, unless you buy the whole visit for a private tour in English (currently, 105EUR per cave -not per person-). https://cuevas.culturadecantabria.com/en/