If you are traveling by TGV (high speed train) from Paris or another major European city, you should travel to Agen, which is the nearest TGV station. You can then rent a car near the train station and drive to Pech Gris in Salles. It takes about one hour. If you don't rent a car, you can transfer to a local train in Agen that will take you to Monsempron-Libos, which is about 10 minutes from Pech-Gris. This is very easy to do, as the platforms and trains are clearly marked (and the train that goes to Monsempron-Libos is marked "Monsempron-Libos"). Just make sure that you purchase your ticket at the ticket counter before boarding the train, and let us know when you'll be arriving so we can pick you up!