A vertiginous 654-step staircase descends 110m of sheer cliff to the Grotta di Nettuno, an underground fairyland of stalactites and stalagmites. If you don’t fancy the staircase, there are ferries from Alghero – Traghetti Navisarda, departing hourly between 9am and 5pm from June to September, and four times daily in the rest of the year. Otherwise, there’s a daily bus from Via Catalogna (€2, 50 minutes) which departs Alghero at 9.15am and returns at midday. From June to September, there are two extra runs at 3.10pm and 5.10pm, returning at 4.05pm and 6.05pm.