Portugal has the oldest appellation system in the world, the Douro Valley. This region and Vinho Verde region, in the Northwest produces some of the world's finest, unique and highest value-added wines. Alentejo and Dão regions produces fruitful flavour wines, suitable for a casual wine drinker.
Portugal has two wine producing regions protected by UNESCO as World Heritage: the Douro Valley Wine Region (Douro Vinhateiro) and Pico Island Wine Region (Ilha do Pico Vinhateira).
Portugal has a large variety of native breeds (about 500), producing a very wide variety of different wines with distinctive personality. The Oxford Companion to Wine describes the country as having "a treasure trove of indigenous grape varieties". With the quality and uniqueness of its wines, the country is a sizable and growing player in wine production, being in the top 10, with 4% of the world market (2003). The country is considered a traditional wine grower with 8% of its continental land dedicated to vineyards. Only the highest mountain peaks are unable to support viticulture. Portugal produces some of the world's best wines, as reflected in its success in international competitions.