Phélan Ségur is a Cru Bourgeois, located in the appellation of St Estephe.
A part of St-Estèphe is separated from Pauillac's Lafite only by a stream.Though St-Estèphe contains some gravel, it is largely renowned for the high clay content of its soils compared with other vineyards on the left bank. These wetter cooler soils favour the Merlot, hence the relatively large proportion of plantings compared neighbouring communes, though Cabernet Sauvignon dominates. The cool soils means the grapes are later ripeing and tend to have high acidities, archetypal St Estèphe is a strong-willed, tannic structured wine to be laid down. The stars of St-Estèphe are Montrose, Cos d’Estournel and Calon-Segur, whilst Haut Marbuzet and Lafon Rochet have been producing excellent value wines over the last few years.