Discovered in 1870, the world's most famous geyser has been reliably been spouting ever since: every 40-120min, between 14 000 and 32 000 litres of boiling water to an average height of 40m. A semi-circular boardwalk with benches surrounds the geyser. During July and August, thousands of people wait patiently here for the next eruption, before heading off to eat in the nearby restaurants.