Abstract: A protective shelter is shown which is installed at least partly in the surrounding earth. The shelter has a metal body with a top, bottom, opposing end walls and opposing sidewalls. The sidewalls of the body are slanted outwardly so as to create a flared bottom region which assists in retaining the body in an installed location with the surrounding earth. A horizontal rib, located on the body exterior at the approximate juncture of the top region and bottom region serves to add structural strength to the body and presents a protuberance which can be set in the earth to further assist in retaining the body in the installed location. An internal bulkhead within the closed interior of the structure provides further structural integrity and protects against falling or crushing loads.