Portugal–Spain border disputed between the two countries for two hundred years. A microstate existed previously on the border called Couto Misto. Districts on the Portuguese side of the border from North to South: Provinces on the Spanish side of the border from North to South: Portugal and Spain signed the Schengen Agreement in June 1991 which came into effect on 26 March 1995, making Portugal and Spain part of the Schengen area and thus the border then became an Open border. Portugal has since reintroduced border checks several times along the border with Spain, during the UEFA Euro 2004 championships, during the
History of Portugal 2014. Later Neanderthals roamed the northern Iberian peninsula and a tooth has been found at Nova da Columbeira cave in Estremadura. Homo sapiens sapiens arrived in Portugal around 35,000 years ago and spread rapidly throughout the country. Pre-Celtic tribes inhabited Portugal leaving a remarkable cultural footprint. The Cynetes developed a written language, leaving many stelae, which are mainly found in the south of Portugal. Early in the first millennium BC, several waves of Celts invaded Portugal from Central Europe and intermarried with the local populations to form several different ethnic groups, with many tribes. The Celtic presence in Portugal is