Petrus is easily Pomerol's most important wine, and is one of the most notable estates in Bordeaux. The Merlot-based wine comes from an 11.4-hectare (28-acre) vineyard in the eastern part of the Pomerol appellation, and is known for being rich and powerful, with characteristics of chocolate, spice and black fruit. Petrus is one of the world's most collectable and expensive wines.
The original 7-hectare (17-acre) vineyard is located on a mound where the soil is almost all clay, unlike nearby properties where there is more gravel or sand in the soil. The high clay content is particularly suitable for Merlot – a unique second layer of dense blue clay forces root systems to spread sideways. This feature is often credited with giving Petrus its soft but abundant tannins. The remaining vineyard was acquired from neighboring Château Gazin in 1969.