Navel oranges are sweet oranges that develop a small second fruit within the larger fruit at the blossom end of the orange which is at the end opposite the stem. Where the second fruit develops is an indentation that looks like a human navel and thus the name. The Washington navel orange is the original and best known navel orange. Other navel orange varieties include Cara Cara, Fukumoto, Lane Late, Robertson, Skaggs Bonanza, and Spring.