Wool was once the single most important commodity in the economies of many European countries. England in the 13th century was the greatest producer of raw wool and would only be rivalled only by the sheepwalks of Castile (Spain) developed from the fifteenth century. Great fortunes were made and wars won and lost.

English textile trade grew during the fifteenth century, to the point where export of wool was discouraged. Over the centuries, various British laws controlled the wool trade or required the use of wool even in burials. The smuggling of wool out of the country, known as owling, was at one time punishable by the cutting off of a hand.

The sheepwalks of Castile, known in Spanish as 'Caņadas', shaped the landscape and the fortunes of the meseta that lies in the heart of the Iberian peninsula; in the sixteenth century, a unified Spain allowed export of Merino lambs only with royal permission. The Caņadas were paths over which the sheep would traverse. Normally sheep would go North for summer and return South for winter along these paths which were protected and maintained by the state.

Today of course most of these Caņadas have fallen into disrepair or even disappeared. Nevertheless there has recently been a movement to protect these traditions. Curiously one of the Caņadas passes right through the centre of Spain's capital city, Madrid. Once a year shepherds bring hundreds of sheep along that Caņada and into the centre of Madrid to the amazement of tourists and visitors.