Haut-Médoc is the large southern section of the greater Médoc district of Bordeaux in southwestern France. It accounts for two-thirds of the Médoc peninsula.
The appellation of the same name covers red wines produced within the same zone, but outside of the six communes which have their own AOP. Cabernet Sauvignon and Merlot are the main grape varieties. White wines made in Haut-Médoc AOP vineyards are bottled as Bordeaux Blanc.
The Haut-Médoc zone is home to the "famous four" appellations of Margaux, Pauillac, Saint-Estèphe and Saint-Julien, as well as the less famous Listrac and Moulis. These actually account for the majority of the wines produced within the Haut-Médoc. The more general title is used for vineyards lying outside these communes.
The soil in the Haut-Médoc region is mainly composed of thick gravel layers that have been swept down river over time and now sit on a base of heavy clay. The warm, well-drained gravel terraces provide ideal growing conditions for the late-ripening Cabernet Sauvignon grapes.
Further inland, the soils turn to deep deposits of clay. The Merlot grape variety thrives in such places. In recent decades it has largely usurped Cabernet Sauvignon in these parts of the Médoc. Patches of limestone and sandier soils add diversity to the more widely spread gravels, which otherwise dominate the terroir.
Much of the peninsula is former swamp land reclaimed by Dutch engineers in the 1600s. This was largely prompted by foreign demand for wines from Graves to the south of Bordeaux city, and from Douro in Portugal.
At the northern and western extremes of the Médoc peninsula, wines are produced under the Médoc appellation. These are the most heavily dredged areas of former swamps with little or no gravel. Until the 1940s they were known as the Bas Médoc, as a clearer counterpoint to the Haut-Médoc, but this name was deemed unfairly negative.