The Mera (Maira in Switzerland) is a river in Switzerland and Italy. Its source is near the Maloja Pass, in Graubünden, Switzerland. It flows west through the Val Bregaglia (Bergell) and crosses the Italian border near Soglio. It is joined by the Acquafraggia close to Piuro, and then turns south at Chiavenna, just before it receives the river Liro from the right at Prata Camportaccio.