Cathedral free admission; tour of catacombs 4.50€ ($7.20) adults, 1.50€ ($1.95) children under 15. Guided tour of cathedral 4.50€ ($7.20) adults, 1.50€ ($2.40) children under 15. South Tower 3.50€ ($5.60) adults, 1€ ($1.60) students and children under 15. Evening tours, including tour of the roof, 10€ ($16) adults, 3.50€ ($5.60) children under 15
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