Operation Roast was a military operation undertaken by British Commandos, at Comacchio lagoon in north-east Italy, during the Spring 1945 offensive in Italy, part of the Italian Campaign, during the final stages of Second World War.

Comacchio is a town and comune of Emilia Romagna, Italy, in the province of Ferrara, 48 kilometres (30 mi) from the provincial capital Ferrara. It was founded about two thousand years ago; across its history it was first governed by the Exarchate of Ravenna, then by the Duchy of Ferrara, and eventually returned to be part of the territories of the Papal States. For its landscape and its history, it is considered one of the major centres of the Po delta.