Dilijan is a spa town and urban municipal community in the Tavush Province of Armenia. The town is one of the most important resorts in Armenia, situated within the Dilijan National Park. The forested town is home to numerous Armenian artists, composers, and filmmakers and features some traditional Armenian architecture. The town is often referred to as the Armenian Switzerland or Little Switzerland by the locals.

Sharambeyan Street in the city centre, has been preserved and maintained as the heart of Dilijan's old town, complete with craftsman's workshops, a gallery and a museum. Hiking, mountain biking, and picnicking are popular recreational activities. As of the 2011 census, Dilijan has a population of 17,712. Dilijan is currently the fastest-growing urban settlement in Armenia.

Dilijan lies on the banks of Aghstev River with a length of more than 20 kilometres (12 miles) and at a height of 1,500 metres (4,921 feet) above sea level. The valley is surrounded with the Lesser Caucasus mountains from the north, and the Semyonovka mountain pass from the south. The mountainous areas -mainly the ranges of Bazum and Pambak mountains- are all covered with thick forests occupying a territory of more than 34,000 hectares (84,016 acres). Reaching up the highest peaks of the mountains, the forests turn into Alpine meadows. In addition to Aghstev River, many other tributaries flow through the town.

The forests of Dilijan cover an area of more than 34,000 hectares. For the enrichment of the natural life around Dilijan, the state forest reserve was founded in 1958 to become known as Dilijan National Park later in 2002. Woods cover 94% of the park territory and with around 40 types of trees and 18 types of bushes, being mostly oaks, beeches, hornbeams, maples, elms, willows, etc.

The national park is also rich in its fauna, including brown bear, wolf, marten, otter, lynx, sylvan cat, Persian squirrel, sylvan dormouse, hedgehog, chamois, European red deer, wild hog, pheasant, quail, partridge, Caspian turkey, culver, white-tailed eagle, lammergeyer, pygmy eagles, golden eagle, hawk and others.

Lake Parz is one of Dilijan's most attractive natural sites. It is situated in the northern part of the town at a height of 1,400 metres (4,593 feet) above sea level. It has an area of 2 hectares (5 acres) and an average depth of 8 metres (26 feet).

To the east of the Lake Parz, at a distance of 3 kilometres (2 miles) from Gosh village, Lake Tzlka is located at a height of 1,500 metres (4,921 feet). Aghstev River with its tributaries passes through the town and the surrounding forest. Its origins are from the northwestern part of the Pambak mountain range, at a height of 2,980 metres (9,777 feet). Aghstev River has a length of 133 kilometres (83 miles). Many tributaries flow into Aghstev such as Bldsan, Ghshtoghan, Haghartsin and Getik rivers.