Lough Melvin is one of Ireland's most extraordinary and ecologically significant fishing destinations, straddling the border between County Leitrim in the Republic of Ireland and County Fermanagh in Northern Ireland. Stretching approximately 12 kilometers in length and nearly 3 kilometers at its widest point, this post-glacial lough covers a surface area of roughly 21.25 square kilometers. The lake reaches a maximum depth of 45 meters in a basin near its southeastern edge toward Rossinver, while the average depth is approximately 10.9 meters. A substantial 46% of the lake is less than 5 meters deep, creating extensive shallow areas — particularly around the lake's several islands, including Inishtemple, Inishkeen, Inishmean, Inisheher, Gorminish, and Bilberry Island. The water quality is rated oligotrophic, meaning it is exceptionally clear and nutrient-poor — conditions that support the remarkable and unique assemblage of wild salmonids that have made this lough world-famous. Lough Melvin drains southward through the River Drowes, which flows into Donegal Bay. The lake can be reached from Sligo via the N15 road toward Donegal, approximately a 45-minute drive, with a turn onto the T54. From Enniskillen, take the road southwest toward the border settlements of Garrison and Rossinver.