I will be in Portugal in August and am thinking I will stay 5-7 days following a few weeks in Spain. If I fly into Lisbon, is it feasible that I could make my way North to the Basque region and also South in that amount of time? I want to pack in as much as I can but also don't want to exhaust myself. What is the best way to cover a lot of area? A combination of flying and train? I've only been to Europe a few times so am not completely familiar with the best types of transportation.