MAD Architects have restored Japan's historic Kiyotsu Gorge Tunnel as a permanent art installation, “Tunnel of Light”, coinciding with the 2018 Echigo-Tsumari Triennale. The art event hosts approximately 160 artworks across 200 villages, inhabiting abandoned spaces as sites for interaction. Located in the Niigata prefecture, the 2,500-foot long passageway cuts through rock formations to offer visitors panoramic views of Japan's mountainous snow country. 

The firm's scheme for this historic lookout consists of transforming several points along the tunnel as spaces for interaction with art and nature. 

Upon approaching the tunnel, a small wooden hut has been constructed to serve as the café and souvenir shop. Inside the pitched cedar roof on the upper level is a hot spring foot spa.

The entrance to the tunnel has been restored to its former glory, and leads the way to the newly renovated passage. Originally illuminated through natural means, it has been outfitted with a series of different colored lights which define each lookout point along the tunnel. 

The first of the lookout point renovations is the “Invisible Bubble”. The capsule-like structure mirrors the silhouette of the tunnel itself while also reflecting its surroundings.

'Dew drops' are scattered along the curvature of the second lookout point. “The Drop” is a series of reflective openings functioning as mysterious windows to visitors. 

The culmination of the restoration is expressed in the form of the “Light Cave”. Semi-polished stainless steel lines the tunnel, drawing the distinct rock formations, lush greenery, and turquoise water of the treasured terrain, into the enclosed space.