The Jet d'Eau is a large fountain located on the Lake Geneva in Geneva, Switzerland. It was originally built in 1886 as a safety valve for a hydraulic power network but has since become a symbol of the city. The fountain shoots water 140 meters into the air and is visible from various points around the lake. The Jet d'Eau operates year-round, although its height can vary depending on weather conditions. It uses approximately 500 liters of water per second and is illuminated at night, making it a popular attraction for both locals and tourists visiting Geneva.