Mulroy Bay is the most convoluted of the marine inlets in north-west Ireland. It is approximately 12 km long in a north-south direction. The entrance to the bay is a narrow embayment leading to a winding entrance channel 10 km in length. This channel varies in width and depth, with three significant narrows only 100–150 m across, where the current reaches maxima of 3-5 knots. It opens into the Broad Water, an open shallow sea lough 8 km from north to south and 2.5 km from east to west, generally less than 20 m in depth and with many small rocky islands and islets.
- "logainm.ie - Bunachar Logainmneacha na hÉireann - Placenames Database of Ireland". logainm.ie. Retrieved 13 January 2014.
- "Donegal". libraryireland.com. Retrieved 13 January 2014.
Mulroy Bay has extensive Fish and Shellfish farming operations. Mussels, Scallops and Salmon are grown on a commercial basis.