A little too late to travel from Barcelona, but anywhere in the province of Teruel or the east part of Guadalajara is inside totality area, will have great weather, clear skies and is endemically underpopulated, so, even with eclipse-chasers coming for the occasion, it will be orders of magnitude less crowded than the coast.
As for myself, I'll be watching it from here: https://theeclipse.app/2026-total/maps/default?lng=-3.562706...