Abbey ruins at Villers-la-Ville
In 1146 a dozen monks and some lay brothers, with the blessings of St Bernard (not the dog!) headed to what is now Belgium and founded the abbey.
It had been neglected and then revitalized during its second golden age in the 1800s where some of the buildings were modernized.
Now in ruins (but pretty ruins!), you can walk through over 800 years of history by visiting the abbey and its grounds and some "still standing" buildings for a few euros.