Saint-Nicolas is a municipality of Wallonia located ine the province of Liège, Belgium. It is effectively a part of the greater Liège conurbatio…Saint-Nicolas is a municipality of Wallonia located ine the province of Liège, Belgium. It is effectively a part of the greater Liège conurbation stretching west from Liège city centre towards Liège Airport. As of 1 January 2006 Saint-Nicolas had a total population of 22,666. The total area is 6.84 km² which gives a population density of 3,313 inhabitants per km². It has the highest population density of any Belgian municipality outside the Brussels-Capital Region.