Toulouse

Toulouse needs 2 days: touring the Cité de l'Espace, the theme park dedicated to space exploration with a full-size replica of the Ariane 5 rocket, on one, and visiting the Basilica of Saint-Sernin, the largest Romanesque church in Europe, on the other. April-June and September-October bring the mildest weather. It's cheaper than Paris. It's known as the 'Pink City' for the color of its terracotta bricks, and it's Airbus's European headquarters, with the highest concentration of aerospace jobs on the continent.