The current municipality of Hannut came about as the result of the administrative merger of the town with 17 of the surrounding villages: Abolens, Avernas-le-Bauduin, Avin, Bertrée, Blehen, Cras-Avernas, Crehen, Grand-Hallet, Lens-Saint-Remy, Merdorp, Moxhe, Petit-Hallet, Poucet, Thisnes, Trognée, Villers-le-Peuplier and Wansin.
The old town, famous for its cattle market, was largely developed in the 19th century, but in its layout displays some traces of older ramparts. The Church of St. Christopher with its medieval tower is the oldest monument in the centre. The town has retained some major heritage elements from each period, such as the Mottin and Snyers châteaux as well as a number of older houses. But Hannut is also made up of a very large number of villages which are distributed towards the Geer and Mehaigne valleys.
The region of Hannut is a transitional region between the Hesbaye-Liège and the Hesbaye-Brabant. The villages are centred around a church and often also feature a château or manor farm. There are fewer courtyard farms from the Ancien Régime in neighbouring villages in the Liège region. In many cases, the remains of these farms are preserved in the old courtyards adjoining the château and/or farm belonging to an abbey or chapterhouse, which owned a large proportion of the land.