Harmanec Tunnel, Railway tunnel in the District of Banská Bystrica, Slovakia

The Harmanec Tunnel, also known as the Čremošniansky Tunnel, is a single-track railway tunnel in the District of Banská Bystrica, Slovakia. It runs under the Malý Šturec pass between the Veľká Fatra and Kremnica mountains, linking the villages of Harmanec and Čremošné.

Construction took place between 1936 and 1940 using the Austrian tunneling method. The tunnel was renamed several times: after Dr. Edvard Beneš in the late 1930s and after Andrej Hlinka during World War II.

The tunnel is known locally by two names: Čremošniansky, after the village on one side, and Harmanec, after the village on the other. People in the area often refer to it simply as the big tunnel, and its portals are familiar landmarks on the mountain paths.

The tunnel is an active railway line, so access inside is not allowed; you can see the portals from nearby paths. The surrounding mountain area has marked trails, and sturdy shoes are useful on the uneven ground.

A large vertical ventilation shaft stands roughly in the middle of the tunnel. It was originally fitted with fans for steam trains, and today it clears exhaust from diesel locomotives, controlled by the stationmaster in Čremošné.