Chaves is a city and a municipality in the north of Portugal. It is 10 km south of the Spanish border and 22 km south of Verín (Spain). The population of the entire municipality in 2011 was 41,243, in an area of 591.23 km2. The municipality is the second most populous of the district of Vila Real. With origins in the Roman civitas Aquæ Flaviæ, Chaves has developed into a regional center. The urban area or city proper has 17,535 residents (2001).

Verín is a town and municipality in the southeast of the province of Ourense, in the autonomous community of Galicia, Spain. The population of the municipality is about 14,433. It is located 70 kilometers east of the provincial capital of Ourense and 15 kilometers north of the Portuguese city of Chaves. The Tâmega River flows through the town. In the Middle Ages it was known as Santa María de Verín.