Geysir is a famous hot spring in Iceland's Haukadalur Valley, known for its geysers and hot springs. While Geysir itself doesn't erupt much these days, nearby Strokkur puts on a show every 5-10 minutes, shooting water up to 40 meters high. You can also check out bubbling mud pots and fumaroles in the area. And if you're feeling fancy, there are hotels and restaurants nearby for a cozy stay.