The specific economics of the Camino de Santiago for budget travelers, because it's one of the most well-known multi-week walks.

The routes: the Camino Francés (French Way, 800km from Saint-Jean-Pied-de-Port to Santiago) is the main route. The Camino Portugués (600km from Lisbon or 200km from Porto) is shorter and less crowded. The Camino del Norte (coastal route, more rugged) is longer but beautiful.

Accommodation: the albergue (pilgrim hostel) system provides dormitory accommodation along the entire Camino Francés for €8-15/night. Municipal albergues (run by local governments) are cheapest at €5-10/night but fill first; arrive before 2pm. Private albergues are €12-18/night but take reservations.

Food: the pilgrim menu (menú del peregrino) is a fixed-price meal at restaurants along the route for €10-14. Typically 3 courses with wine. Available at lunch and dinner throughout the route. This is the correct way to eat on the Camino — far better value than ordering à la carte.

Total budget for the Camino Francés (30-35 days walking): €700-1,000 all-in including accommodation, food, and incidentals. This is approximately €23-30/day.

Gear investment upfront: good boots are the only essential investment. Cheap boots cause blisters that end Caminos. Budget €100-150 for legitimate trail shoes, purchased and broken in before you go. Bring only a 20-25L day pack with a sleeping bag liner.