The Furka Base Tunnel is a Swiss railway base tunnel on the Matterhorn Gotthard Bahn's Furka–Oberalp line, an east–west railway connecting the cantons of Valais and Uri. Its west portal lies east of Oberwald (VS), at 1,390 m (4,560 ft) above sea level and its east portal lies south of Realp (UR), at 1,550 m (5,090 ft).

The Matterhorn Gotthard Bahn is a narrow gauge railway line and a railway company in Switzerland. The track width is 1,000 mm. It was created in 2003 through an amalgamation of Furka Oberalp Bahn (FO) and BVZ Zermatt-Bahn (BVZ). The name comes from the Matterhorn and St. Gotthard Pass.