Lough Neagh is situated in the centre of Northern Ireland. It is the largest freshwater lake in the United Kingdom covering an area of 383 km2 with a longest length of 30.5 km and narrowest width of 12.1 km across the middle. The lake is very shallow for its size with an average depth of 8.9 metres. At its deepest point it extends down to 34 metres.
The 125 km shoreline is mostly exposed with wave-beaten rocks and stones but there are also some sheltered, sandy bays with better developed marginal vegetation including some reedbeds.
Rivers flowing into Lough Neagh drain about 43% of Northern Ireland, plus part of County Monaghan in the Republic of Ireland.
The pdf document below shows a map of the Lough Neagh drainage area.
Lough Neagh Lake Catchment Map