Madeira is made on the volcanic Portuguese island of the same name, fortified with grape spirit and then deliberately heated — either in hot attics (estufagem) or, for the finest examples, simply left to age slowly in warm island warehouses over years or decades (canteiro). That heat and oxygen exposure, which would ruin most wine, is what gives Madeira its distinctive caramelised character and near-total resistance to spoilage — an opened bottle can last for months or years.

Key grapes: Sercial, Verdelho, Bual, Malmsey (Malvasia)