La Mola is the promontory on the north side of the entrance to Mahón harbor. The anchorage at Cala Taulera is protected by it. What you can't see from the boat is the huge fortress that sits atop La Mola.
Wow, what a fortress! We've seen many forts and fortifications in our travels, but nothing else comes close to the size and complexity of the Fortress of Isabel II. The fortress and associated military buildings cover the whole point, and the fortress itself was built using a combination of state-of-the-art plans for such structures. It has two moats on the outside, and in case the main defenses are breached, there's an inner fortification with its own moat as a fallback position.
Besides the fort itself, the views are spectacular. La Mola is one of the highest points on the island, and you can see for miles.