Fray Bentos is the capital city of the Río Negro Department, in south-western Uruguay. Its port on the Uruguay River is one of the nation's most important harbours. The city hosts the first campus of the Technological University, beside the historically relevant industrial complex Anglo, a World Heritage site. One of the biggest pulp mills in the world is situated close to Fray Bentos and the Libertador General San Martín Bridge; it was the center of the largest political dispute between Uruguay and Argentina during the 21st century.