Zonnestraal is a former sanatorium located in the Netherlands, specifically in the town of Hilversum. Built in the 1920s, it was designed by the architect Jan Duiker and is known for its modernist style. The building was intended to provide a healing environment for tuberculosis patients, featuring large windows and open spaces to maximize sunlight exposure. Today, Zonnestraal is recognized as a significant example of modern architecture and is part of the UNESCO World Heritage list. The site has been repurposed for various uses, including residential and cultural activities, while preserving its historical and architectural value.