A slipway has recently been built (2005) at Port Mòr and this allows vehicles to be driven on and off the Caledonian MacBrayne ferry, MV Lochnevis, which links Muck with its neighbouring Small Isles of Canna, Rùm and Eigg, to the mainland port of Mallaig (2 1/2 hours away). However, visitors are not normally permitted to bring vehicles to the Small Isles. During the summer months the islands are also served by Arisaig Marine's ferry MV Sheerwater from Arisaig, 10 mls south of Mallaig.
The island's main hill is Beinn Airein (137m). Muck is also known for its seal population, and for the porpoises in the surrounding waters. The name may derive from the Gaelic word for porpoise. An earlier owner, who disliked the name, attempted to persuade Samuel Johnson and James Boswell that the authentic name was Isle of Monk.