Hi I am driving down to Tortosa at the end of March ,and still planning the route  down.
The last time I drove down i went via the Millau Bridge - la jonquera- Barcelona route  down and return route was via the Cadi Tunnel - Tunnel du Puymorens- Toulouse ,I was thinking about taking the Cadi route again ? but thinking Carretera Lleida-Vielha Tunnel, route might be better less steep hills ? as the trucks use this
Any advise appreciated ;D