Sweet treats in the heart of Spain

The ancient Chinese invented it, medieval Arabs adapted it and modern Germans made it a winter staple. But the world's finest marzipanthat oh-so-sweet confection of sugar and almond pasteis made by the cloistered nuns of holy Toledo, Spain. The city, once capital of much of the Iberian peninsula, has several other tourist draws: one of the world's finest Gothic cathedrals, exquisite gold-inlaid damascene jewelry and magnificent swords. But the Spanish themselves say no Christmas celebration is complete without the nun-made sweets.

The best stuff is produced by nuns of the convent of Santo Domingo el Antiguo. The Cistercian...