Fort William (Gaelic: An Gearasdan, "The Garrison") is the largest town in the west highlands of Scotland. Originally based around the still-extant village of Inverlochy, the town lies at the southern end of the Great Glen, on the shores of Loch Linnhe and Loch Eil. It is close to Ben Nevis, the highest mountain in the British Isles, and the beautiful Glen Nevis. The town is a major tourist centre with Glencoe just to the south, and Glenfinnan to the west, on the Road to the Isles. It is an important centre for hillwalking and climbing due to its proximity to Ben Nevis and other mountains. It is also well known for its nearby famous Downhill Mountain Bike Track and its connection to the Great Glen Way; a cycle way from Inverness to Fort William through the Great Glen.

Historically, this area of Lochaber was strongly Cameron country, and there were a number of mainly Cameron settlements in the area (such as Blarmacfoldach). The nearby settlement of Inverlochy was the main settlement in the area before the building of the fort, and was also site of the Battle of Inverlochy.

However, the town is not of local origin. It grew up as a settlement next to a fort constructed to control the population after Oliver Cromwell's invasion during the English Civil War, and then to suppress the Jacobite uprisings of the 18th century. The fort was named "Fort William"' after William Of Orange, and the settlement that grew around it was called "Maryburgh", after his wife. This settlement was later renamed "Gordonsburgh", and then "Duncansburgh" before being renamed "Fort William", this time after "Butcher" Cumberland. Given these origins, there have been various suggestions over the years to rename the town (for example, to "Invernevis"). These proposals have led to nothing as of yet.

During World War II, Fort William was the home of HMS St Christopher which was a training base for Royal Navy Coastal Forces.

Fort William is the end point of the West Highland Way, a long distance footpath which runs 95 miles across the Scottish Highlands from Glasgow, and the start/end point of the Great Glen Way, which runs between Fort William and Inverness.

The town is centred on the High Street, which was pedestrianised in the 90s. Off this there are several squares. Monzie Square (named after the Cameron Campbells of Monzie, Perthshire, former landowners in the town), Station Square, where the long-since demolished but often lamented railway station used to be, Gordon Square (named for the Gordons, who owned land where the town now stands in the late 1700s, during which time the town was named Gordonsburgh), and Cameron Square.

Just outside the town is a large aluminium plant, powered by the Lochaber hydro-electric scheme, in its day the biggest tunnelling project in the world. This was formerly served by the Lochaber narrow gauge railway.

The West Highland Line passes through Fort William. Owing to the difficult terrain in the area, the line from Glasgow, to the south, enters from the northeast and trains from Glasgow to Mallaig, the terminus of the line, have to reverse at Fort William railway station.

The Caledonian Canal connects the Scottish east coast at Inverness with the west coast at Corpach near Fort William.

Each year, Fort William attracts hundreds by hosting the UCI Mountain Biking World Cup on its famous track just outside the town. In 2007 it is bringing two cruise ships into the harbour to help accommodate the many visitors.

In a celebration of mountains and the culture that surrounds them, and in recognition of the importance of climbing and walking tourism to the town, the Fort William Mountain Film Festival is held there each year. For a number of years this volunteer led festival has concentrated mostly around film but, starting in the Year of Highland Culture - Highland 2007, its scope was widened, and it dropped the 'film' from its title.

Fort William has two major shinty teams, Fort William Shinty Clu