CREST, a town of south-eastern France, in the department of Drôme, on the right bank of the Drôme, 20 m. S.S.E. of Valence by rail. Pop. (1906) town, 3971; commune, 5660. It carries on silk-worm breeding, silk-spinning, and the manufacture of woollens, paper, leather and cement. There is trade in truffles. On the rock which commands the town stands a huge keep, the sole survival of a castle (12th century) to which Crest was indebted for its importance in the middle ages and the Religious Wars. The rest of the castle was destroyed in the first half of the 17th century, after which the keep was used as a state prison. Crest ranked for a time as the capital of the duchy of Valentinois, and in that capacity belonged before the Revolution to the prince of Monaco. The communal charter, graven on stone and dating from the 12th century, is preserved in the public archives. Ten miles south-east of Crest lies the picturesque Forest of Saon.