Kranj is the fourth-largest city in Slovenia, with a population of 37,941 (2020). It is located approximately 20 kilometres (12 miles) northwest of Ljubljana. The centre of the City Municipality of Kranj and of the traditional region of Upper Carniola (northwestern Slovenia) is a mainly industrial city with significant electronics and rubber industries.

The nucleus of the city is a well-preserved medieval old town, built at the confluence of the Kokra and Sava rivers. The city is served by the Kranj railway station on the route from Ljubljana to Munich, Germany (via Jesenice and Villach, Austria) and a highway. Slovenia's national airport, Ljubljana Jože Pucnik Airport (in Brnik) is also very close to Kranj, considerably more so than its nominal client, Ljubljana.

In Kranj, the Kokra cuts deeply into the conglomerate, forming a canyon 40 meters (130 ft) deep. Kosorep, on the northern outskirts of Kranj, is a picturesque site along the river. Parts of the canyon can be reached by a walking trail. Below Kranj, at Drulovka, the Sava forms a 40-meter (130 ft) deep canyon with conglomerate on both sides. Due to the dam for the Mavcice Hydroelectric Plant, the river's flow there is very slow.