The site of a settlement is the place where the settlement initially grew. The site of a settlement can be thought of as an advantage that a particular place had.
The situation of a settlement is where it is located in relation to other settlements. Even if a settlement had very good site advantages - if it was not in a good situation then it would not grow and develop.
There are many examples of defensive sites across Northern Ireland. This monastery was sited on Devenish Island to guard against Viking invasions. The round tower provided refuge for the inhabitants of the monastery in times of attack. Devenish is no longer occupied, but other defensive settlements like Enniskillen have continued to grow and develop. Enniskillen castle was built 600 years ago to guard one of the few passes into Ulster. The town's defences were further improved in the 18th century under threat of French invasion.
In the past it was very difficult to build bridges so the narrowest point in a river was often selected as a crossing point. Coleraine is a good example of a narrow bridging point. The city grew up around the narrowest crossing point on this section of the River Bann.
Omagh was sited in an area of good water supply on the banks of the River Strule. As well as providing defence, a river situation provided access to water for cooking and cleaning. Rivers were also used for the transport of goods to and from a site.
Newtownstewart is surrounded by lush, fertile farmland. People would have moved here to farm the land and keep animals. A village like Newtownstewart would have served as a market place where local people came to trade their goods, produce and livestock.
Settlements were often established in areas protected from the extremes of weather. Newcastle, resting at the foot of Slieve Donard, has developed in the shelter of the Mourne Mountains.
Newry is the meeting point of several important routes between Belfast, Dublin, Armagh and the routes around the Mournes. It is also the site where the Clanrye River flows into Carlingford Lough. Newry has a very good situation in relation to other settlements and is described as a nodal point.
A settlement like Belfast, which has more than one of these site advantages, is more likely to grow and develop.
Belfast grew up around the narrowest bridging point of the Farset river, where High street is today. The river provided a supply of fresh water to the settlement's inhabitants. The Lough and the Connswater, Lagan and Blackstaff rivers provided access to water transport routes. Shelter was provided by the surrounding Divis, Black and Cavehill mountains and the Castlereagh and Hollywood hills. The fertile farmland of the Lagan valley was another advantage. Belfast has developed into a nodal point being the point where rail, road and sea networks meet.