Pomelo

Also sometimes called shaddock, the pomelo, fruit of Citrus maxima, is the largest of the citrus fruits; pomelos can weigh more than 15 pounds. The tree is native to Southeast Asia. The fruit has a very thick skin, and the flesh of the fruit is less juicy than that of grapefruit. (Grapefruit is a hybrid created in Barbados over two hundred years ago by cross-breeding the pomelo and the mandarin orange.)