Neptune's Grotto and Capo Caccia

Neptune's Grotto (Grotta di Nettuno) lies 23 km west of Alghero at the foot of the dramatic Capo Caccia headland, and reaching it is half the experience. The most relaxed approach is the 40-minute boat trip from Alghero's port, which skirts the 186-metre limestone cliffs and the Porto Conte Natural Park, where griffon vultures ride the thermals and dolphins are sometimes seen. The more adventurous arrival is by car to the Capo Caccia car park followed by a descent of the Escala del Cabirol, a 654-step staircase carved into the cliff face, spectacular but demanding on the return climb. Inside, the cave extends roughly 2.5 km into the rock, though the guided walkway covers a smaller loop past forests of stalactites and stalagmites and the still expanse of Lake Lamarmora, one of the largest saltwater lakes inside a European cave. Entry is by guided tour only and costs around €13. A satisfying full day pairs the grotto with time in the Porto Conte park and the cliff-top viewpoints over the Mediterranean. A practical morning plan is to drive out to Capo Caccia early, walk down the staircase for the first cool tours of the day, then return to Alghero for a late lunch of the city's celebrated lobster, aragosta alla catalana, in the old town. Alternatively, an afternoon boat trip from Alghero combines the cliffs and the cave in a single relaxed outing. Travellers who prefer to descend the stairs but spare their legs the climb can take the staircase down and the boat back, the combination many regulars favour. The grotto and boats operate from April to October, with daily departures in high summer. Strong Maestrale winds can cancel boat services, so checking conditions the morning of travel avoids a wasted trip. Early or late in the day brings softer light for photographing the cliffs and fewer people inside the cave. Visitors descending the staircase should wear proper shoes and carry water, as the 654 steps back up are strenuous in the heat.