Anchor Porter is a unique dark brew, which was introduced by Anchor in the early 1970s. Anchor Porter, like all of Anchor Brewing Company‘s products, is brewed with only natural ingredients. Specially roasted dark malts are used, along with a top-fermenting yeast. The brew is hopped at a very high rate, and is naturally carbonated to produce an intensely rich flavor and thick creamy head. -from anchorbrewing.com