The best way to get to the mainland is by the ferry between Oban with Castlebay and Lochboisdale. There are around six sailings on the trianguar route each week from Oban and Lochboisdale, and most sailings call at Castlebay en route both ways.  The journey between Oban and Castlebay takes just over 5 hours and is a great way to enjoy the beautiful scenery on route.