Switzerland is largely self-sufficient in apple production, with only five percent being imported. The country consumes about 16 kilograms of apples per year per person, with Gala being the most popular variety. The cantons of Thurgau, Valais, and the Lake Geneva region are the main areas for apple cultivation. Switzerland has advanced apple storage technologies, allowing storage for several months or years. Sursee, in the canton of Lucerne, has a fruit hall that stores several thousand tons of apples from over 20 varieties. Normal storage of apples should be in a cool, dark, and not too dry basement. However, apples emit ethylene ripening gas, which can accelerate the ripening of neighbors.