Cadw Open Doors event in September (‘Free entry to many ‘unseen gems’ that are not usually open to the public along with very well known Cadw sites; a chance to really discover the inside stories of these incredible sites with guided tours on offer at a number of venues’). Events in Monmouthshire: HERE
Cadw monuments require you to register for free tickets via Eventbrite in order to enter some sites, please visit the page and register for yours today: EVENTBRITE