Qualibou, also known as the Soufrière Volcanic Center, is a 3.5 X 5 km wide caldera on the island of Saint Lucia that formed approximately 32–39,000 years ago. Sulfur Springs is an active geothermal area located roughly in the center of the caldera. Last eruption was in 1766 so it’s more than 250 years since it’s last eruption

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