Nairn (/ˈnɛərn/; Scottish Gaelic: Inbhir Narann) is a town and former royal burgh in the Highland Council area of Scotland. It is an ancient fishing port and market town around 17 miles (27 km) east of Inverness, at the point where the River Nairn enters the Moray Firth. It is the traditional county town of Nairnshire.

At the 2022 census, Nairn had a population of 9,394, making it the third-largest settlement in the Highland Council area, behind Inverness and Fort William. Nairn is best known as a seaside resort, with two golf courses, beaches, a community centre and arts venue, a small theatre (The Little Theatre) and a small museum, providing information on the local area and incorporating the collection of the former Fishertown museum.

The History of Nairn is a broad and diverse topic spanning its Palaeolithic and Mesolithic roots before recorded history, to the Picts and the visitation of Roman general Agricola. Its possible founding under the name Ekkailsbakki by Sigurd, Earl of Orkney, its royal burgh status under David I, its strong links to monarchs and regents of Scotland and its strategic position in multiple wars and famine.

Formerly part of the Supercontinent of Rodinia as evidenced by the discovery of Dalradian Supergroup rocks, Nairn encompasses a 2+5⁄8-by-1+1⁄2-mile (4-by-2.5-kilometre) position on the mouth of the River Nairn and is fronted by the North Sea at the Moray Firth with two extensive beaches. The east beach being predominantly sand with dune vegetation (such as marram grass) and the west having more rock though becoming more sand as it reaches the river mouth. The Culbin Sands forms part of one of the most extensive areas of stabilised blown sand in Britain. The soil by the coast is largely a thin and loose organic layer developing directly on the sand and this has been strengthened in areas such as Culbin for forestry.

The town itself is predominantly flat rising from sea level to 40 feet (12 metres) in Fishertown and the majority of the town sitting at 65 feet (20 metres) above sea level. Sections of Nairn do reach as high as 95 feet (29 metres) near Balblair. The low ground near the coast is fertile and the soil rich free loam over sand or gravel. In the town thin, rather acidic soils are present throughout. The alluvial plain has shown Permo-Triassic sandstones, thick accumulations of Jurassic sandstones and dark shales, and erosion by ice sheets. Excavation can reveal dark, muddy glacial deposits, with occasional fossils and shells.

As the land rises south we see Conifer forests and on the higher slopes we see heather moorland and montane vegetation. The wider Nairnshire and Moray area is 28% woodland, one of the most-wooded areas in Britain.

The Bar at Culbin appears to be migrating westwards at about 1.5 km per century, leaving a broad salt marsh in its lee. The soft coast also includes the flat, sweeping, wide and gently undulating Culbin Sands dune system, which culminates in the Lady Culbin dune (over 30m high), the largest in Britain.

— Turnbull Jeffrey Partnership, "NatureScot Review 101 – Moray and Nairn landscape character assessment"