THE ruins of Fountains Abbey, Britain's best preserved and largest Cistercian monastery, near Ripon, attracted over 414,000 visitors last year, an increase from 373,000 the year before. The National Trust site, which is also a world heritage centre was built in 1132 and operated as an abbey for 407 years becoming one of the wealthiest monasteries in the country. Fountains is one of the top ten most visited Trust sites across Britain, the Giants Causeway in Northern Ireland is the most popular with over 665,000 visitors last year.