planning a trip to pyrenees, basque, and green spain in september. we have 3 weeks. would fly to barcelona, rent a car and begin travelling hoping to move back and forth between france and spain. is there a problem taking a spanish rental in and out of france? would drop off again in barcelona as that is where we fly out from again. any thoughts on this plan? wondering about the pyrenees sept. to early october and weather for traveling and walking. we don't anticipate getting as far as we would like in 3 weeks, may have to settle on pyrenees and spanish basque saving further west for another trip. we did spend 4 days in barcelona 2 years ago, loved the city but don;t need to stay very long again. thanks for any help in this preliminary planning.

There will be no problem taking the car back and forth cross the border. Just be sure the car rental agency knows you're going to do it so you have the proper insurance card in the car. there should not be any extra charge.

Spanish law apparently dictates that if you need eyeglasses to drive as per license you must carry a spare pair at all times when driving

Some Spaniards confirmed this and said roadside checks even check on this

Thank you Palenq, I shall remember this for our next trip to Spain.
Coming in and out of Spain of course we do it all the time. No problem at all....

No problem crossing the border with a rental car. We did the same just recently.

Weather in Sept./Oct. will be perfect: blue skies, sunshine, warm but not hot.

Plan your trip leisurely. There are many interesting destinations in the area. Make sure to see Ceret, Carcassonne, Biarritz, Donostia.

If you are coming from the States, then there is no problem crossing back and forth between Spain and France as long as you are using the correct car rental company. I highly recommend Auto Europe, Avis and Hertz.

The weather in the Pyrenees from September to mid-October is generally quite mild, especially along the Pyrenees Orientals. You should be able to cover a lot of ground in three weeks.