Téléphérique-tunnel de Fleissalm, Aerial tramway and tunnel in Heiligenblut, Austria

The Tunnelbahn Fleißalm is a group pendulum aerial tramway in the Heiligenblut ski area that runs almost entirely through a water gallery. Its lower station at Rossbach (1,753 m) and upper station at Fleißalm (1,809 m) are 1,650 m apart. The route includes a 65 m steel bridge over the Rossbach torrent and a tubular avalanche-protection bridge at the upper end.

The system was built in 1987 by converting an existing water tunnel from a hydroelectric power plant into a passenger transport cable way. This repurposing of industrial infrastructure into a public transport system created a dual-function mountain facility.

The line runs through a water gallery of the Fleiß hydroelectric plant, built for overflow water between Fleiß and Rossbach. In summer the gallery can be flooded up to half a metre, so the railway only operates in winter, when it carries skiers between the Rossbach lifts and the Fleiß–Hochfleiß drag lifts. Waagner Biro developed the system, and in 2021 Frey Austria renewed its electronic controls and fitted the cabins with Wi-Fi and smoke detectors.

The journey takes only a few minutes and carries a limited number of passengers per trip in small cars. Visitors should be aware that the narrow underground passage may cause discomfort for those sensitive to enclosed spaces.

The 1987 Waagner Biro system is officially a "suspended monorail with a haul cable, shuttle operation and a passing loop", but it works as a pulsed aerial tramway: steel rails above the cabins carry them, and rollers on the ground rails keep them upright. It is the only installation of its kind in the world.