Talhas are pitch-lined clay vessels of six hundred litres or more. Grapes go in whole, skins and all, and the wine is drawn from a tap near the base once the cap has fallen — traditionally on St Martin's Day, 11 November.
Vila de Frades keeps the practice alive commercially, and a growing number of serious producers have adopted it. The wines are savoury, faintly saline and quite unlike anything else in Portugal.