April : On Sundays (and Saturday 10 and Monday 12 April) 3, 4 and 5pm From May to the end of June : Every week-end and public holiday at 3, 4 and 5pm July and August : Every day except on Mondays at 3, 4 and 5pm 3€50/pp 2€75/pp (group) 2€50/children under 6 For groups only : any other time by booking with the Tourist Office