Complex sentence: During the Middle Ages, the Cotswolds became prosperous from the wool trade with the Continent, with much of the money made from wool directed towards the building of churches; the area still preserving a large number of large, handsome Cotswold Stone "wool churches".
Split into simpler sentences: During the Middle Ages, the Cotswolds became prosperous from the wool trade with the Continent. Much of this wealth was directed towards the building of churches, the area still preserving a large number of large, handsome Cotswold Stone "wool churches".