CAU CAU Caucau or Cau-cau, comes from the mapuche cawcaw, or common swallow and is the name of a river of 1 km. of length that flows through the northern part of the island Texas, in the beautiful city and region of Valdivia, in Chile (for me the most beautiful in the world). A bridge was built to connect the island with the city of Valdivia and was named after the river. Unfortunately, engineering errors have made it impossible to use this drawbridge optimally and for many years remained closed until it was partially enabled in 2018.