Crater, also Kraytar, is a district of the Aden Governorate, Yemen. Its official name is Seera. It is situated in a crater of an ancient volcano …Crater, also Kraytar, is a district of the Aden Governorate, Yemen. Its official name is Seera. It is situated in a crater of an ancient volcano which forms the Shamsan Mountains. As of 2003, the district had a population of 76,723 people.