Lough Neagh is a freshwater lake in Northern Ireland and is the largest lake on the island of Ireland and in the United Kingdom. It has a surface area of 151 square miles and is about 19 miles (31 km) long and 9 miles (14 km) wide. According to Northern Ireland Water, it supplies 40.7% of Northern Ireland's drinking water. Its main inflows are the Upper River Bann and Blackwater, and its main outflow is the Lower Bann. There are several small islands, including Ram's Island, Coney Island and Derrywarragh Island. The lake bed is owned by the 12th Earl of Shaftesbury and the lake is managed by Lough Neagh Partnership. Its name comes from Irish Loch nEachach, meaning "Eachaidh's lake".

Randalstown is a townland and small town in County Antrim, Northern Ireland, between Antrim and Toome. It has a very prominent disused railway viaduct and lies beside Lough Neagh and the Shane's Castle estate. The town is bypassed by the M22 motorway with junctions at both the eastern and western ends of the town. It had a population of 5,151 people in the 2021 Census.