Douro, Faina Fluvial Labor on the Douro River is a 1931 Portuguese documentary short film. It was the first film directed by Manoel de Oliveira and is a portrait of his hometown of Porto and the labor and industry that takes place along the citys main river, the Douro River. It was first shown at the International Congress of Film Critics in Lisbon on September 19, 1931, where the majority of the Portuguese audience booed. However, other foreign critics and artists who were in attendance praised the film, such as Luigi Pirandello and mile Vuillermoz. Oliveira reedited the film with a new soundtrack and rereleased it in 1934. Again in 1994, Oliveira modified the film by adding a new, more avantgarde soundtrack by Lus de Freitas Branco.
Source: Wikipedia