In the Alpes-de-Haute-Provence department, the Valensole plateau is renowned for the production of lavender essential oil famous worldwide. The lavender distillation process begins when the pre-wilted flower has been loaded and tamped on racks into the massive vats of the still. Inside the vats, water vapor heated to 320°F (160°C) to prevent it from returning to water crosses the vegetable matter in the still, releases and entrains the aromas. Charged with essence, the vapor is then cooled and directed into a heat exchanger, where its temperature drops to ambient temperature. When the vapor has returned to the liquid state, the essential oil, which does not mix with the water, is recovered in an essencier.