The Atlantic island, almost 1,000 kilometers from the Portuguese coast, is known for its very special wine. "Madeira" is a fortified wine, ie a wine enriched with brandy. The alcohol content of Madeira wine is between 17 and 22 percent by volume, depending on the variety. The manufacture of the island's fortified wine dates back to its shipping history. Wines mixed with alcohol survived the long voyages of the Portuguese seafarers to Africa, India and South America better. Approved white wine varieties for the production of Madeira today are Bual, Malmsey, Sercial and Verfelho.