San Miquel de Fai
San Miquel de Fai is a monestary in a spectacular location about 30km north of Barcelona perched on the side of a cliff with waterfalls and caves nearby. Only open Sundays and Festivals but well worth the drive for the view.
To get there head out on the C-69 past Caldes de Montbui and follow the directions from Saint Feliu de Codines. As soon as you leave St Feliu you get this vast vista of high red-stone cliffs and following a windy road you eventually reach the monestary.
The monestary is perched on the cliff side with cliffs above and below with lots of water flowing through gulleys - even in the height of summer. Following a path you pass under a 2-300ft waterfall and look out to the valley below. There are caves to explore and picnic area and playground for the children. You don't actually get to go inside the building (which is still working monestary), but the walk and views make it a great place to visit - completely different to the coast or other Catalan scenery.
The BCN tourist office provides coach trips to get to the abbey if you don't have transport.