The weather is unpredictable at all times of the year, and although the seasons are distinct, they are considerably less pronounced than in interior Europe or the eastern seaboard of North America.
Average daytime maximums in Belfast are 43.7°F (6.5°C) in January and 63.5°F (17.5°C) in July.
The fauna of Northern Ireland is similar to that of Great Britain, with fewer species.
Only the Irish stoat, the Irish hare, and three species of birds are exclusively Irish, although the region is rich in fish, particularly pike, perch, trout, and salmon.
Mesolithic middle stone age inhabitants arrived some time after 8000 , is the Giant's Ring, a henge monument at Ballynahatty, near [Belfast]], which consists of a circular enclosure, 590 feet (200 meters) in diameter, surrounded with an 15 feet (four-meter) high earthwork bank with five entrances, and a small neolithic passage grave slightly off-center.
Ireland was organized into a number of independent petty kingdoms, or tuatha (clans), each with an elected king.With heavy urbanization and industrialization along the Lagan Valley and both shores of Belfast Lough, it is the largest city in Northern Ireland and the province of Ulster, and the second-largest city on the island of Ireland (after Dublin).Other cities include Armagh, Londonderry, Lisburn, and Newry.The volcanic activity which created the Antrim Plateau also formed the eerily geometric pillars of the Giant's Causeway on the north Antrim coast.Also in north Antrim are the Carrick-a-Rede Rope Bridge, Mussenden Temple and the Glens of Antrim.Each king was surrounded by an aristocracy, with clearly defined land and property rights, and whose main wealth was in cattle.Céilí, or clients supported greater landowners by tilling the soil and tending the cattle.There are substantial uplands in the Sperrin Mountains (an extension of the Caledonian fold mountains) with extensive gold deposits, granite Mourne Mountains, and basalt Antrim Plateau, as well as smaller ranges in South Armagh and along the Fermanagh–Tyrone border.None of the hills are especially high, with Slieve Donard in the dramatic Mournes reaching 2782 feet, (848 meters), Northern Ireland's highest point. The whole of Northern Ireland has a temperate maritime climate, rather wetter in the west than the east, although cloud cover is persistent across the region.Environmental issues include sewage treatment, that the European Commission in 2003 alleged was inadequate.The valley of the River Lagan is dominated by Northern Ireland's capital city, Belfast, whose metropolitan area included 276,459 people in 2001, over a third of the population of Northern Ireland.