The geological feature known as a hot spring is characterized by heated groundwater that emerges from the Earth’s crust. Hot springs occur when water seeps deep underground and is heated by geothermal energy, often leading to mineral-rich waters. They can be found in various locations worldwide, frequently associated with volcanic activity. Hot springs are popular for therapeutic bathing and relaxation, attracting tourists seeking their reputed health benefits, particularly in areas like Yellowstone National Park in the United States and Japan's onsen.