Architecture, Building and Structure Design Kaffihus Hringur Coffee Shop by Yuting Zhang Kaffihus Hringur offers a unique, sustainable experience for hikers on the Hverfjall Crater trek. Inspired by the tuff cone volcano, the circular coffee shop is a respite for weary hikers, with a warm, wood-toned interior and stunning views of Lake Myvatn. Sustainability is at the heart of the project, with features such as geothermal heat pumps and rainwater capture. The minimal-staff coffee shop offers a comprehensive sensory experience with a variety of coffee beans grown on volcanic soil.