Despite its name, a Barleywine (or Barley Wine) is very much a beer, albeit a very strong and often intense beer! In fact, it's one of the strongest of the beer styles. Lively and fruity, sometimes sweet, sometimes bittersweet, but always alcoholic. A brew of this strength and complexity can be a challenge to the palate. Expect anything from an amber to dark brown colored beer, with aromas ranging from intense fruits to intense hops. Body is typically thick, alcohol will definitely be perceived, and flavors can range from dominant fruits to palate smacking, resiny hops.
English varieties are quite different from the American efforts, what sets them apart is usually the American versions are insanely hopped to make for a more bitter and hop flavored brew, typically using American high alpha oil hops. English version tend to be more rounded and balanced between malt and hops, with a slightly lower alcohol content, though this is not always the case.
Most Barleywines can be cellared for years and typically age like wine.