The Seelisberg tunnel is a 9’250 m long, double-tube and double-lane road tunnel on the highway N02, connecting Beckenried (NW) with Seedorf (UR). It is the second-longest tunnel between Basel and Chiasso after the Gotthard Road Tunnel. There are cross-passages between the tubes every 300 meters. The tunnel system also comprises the two ventilation stations Rütenen and Büel at the south portal as well as the underground ventilation station Hattig with a vertical shaft and outdoor installations. The assignment comprises the quinquennial main inspections of the tunnel (2013/2018) and the auxiliary structures (2014/2019) as well as several intermittent inspections with the following work packages: Main inspection with visual check, evaluation and assessment of all the 43 components. Intermittent inspections of single, regularly to be tested structural parts as well as their evaluation and assessment. Evaluation and assessment of the monitoring measurements in the contract section Huttegg (segment deformation) and in the Amdenmergel segment of the contract section Rütenen (swelling-induced heaves). The objectives of the condition examination are: Preservation of a sufficient structural and operational safety, Ensuring the suitability for use, Awareness and accountability of the owner, Documentation of the structural condition and its transformation.