While often treated as a type of dessert wine, but it's so vast that it deserves a category on it's own. Made by adding grape brandy to a wine, fortified wines can often be barrel aged for years, and tend to have a much longer shelf life once opened due to the higher alcohol content. Common fortified wines include:

Port. Originates in Portugal but is now produced worldwide, in various styles mostly depending on age, and are usually off dry or sweet. Usually a blend of various grape varietals.

Sherry & Montilla-Moriles. Coming from Andalucia in Spain, it’s traditionally dry, it’s sometimes sweetened and served as a dessert wine. It has various styles based on vinification techniques. Sherry comes from Palomino, while Montilla comes from Pedro Ximenez

Madeira. Originating in the Portuguese Madeira Islands, this type is heated and oxidized by exposing it to air, and comes from various grape varietals & levels of sweetness.

Vermouth. Coming from Italy or France, vermouth is a fortified white wine that’s often flavored with herbs and spices like cloves and cinnamon, and is often categorised as either red/dark or white/dry