The Sahrawi Republic, officially the Sahrawi Arab Democratic Republic (SADR) is a partially recognized state that controls a thin strip of area in the Western Sahara region and claims sovereignty over the entire territory of Western Sahara, a former Spanish colony and later province. SADR was proclaimed by the Polisario Front on February 27, 1976, in Bir Lehlou, Western Sahara, a former socialist liberation force which has since reformed its ideological and political views. The world’s longest cargo train, the Mauritania Railway cargo train, passes through Western Sahara for a small distance on the North eastern corner of Western Sahara to end at Nouadhibou. The transportation through Western Sahara was seriously disrupted during the wars till 1997 between Polisaro and Moroccan forces, when ceasefire was established with UN effort.