It's called Tintern Abbey Cottage. It's in Tintern village, right opposite the Abbey. The view is the main thing. You can see it from the front garden and most of the windows.
It sleeps six. Three bedrooms, two bathrooms. One of the bedrooms is downstairs. It's a detached cottage with its own garden front and back. The back one is enclosed, which is good if you have dogs or kids. The front isn't fenced, so you just get the open view across to the Abbey.
It's a 5 Star place. That means it's been done up to a high standard. It's warm, everything works, and it's got things like a wood burner, a dishwasher, and parking. There's also an electric car charger now.
The stairs are normal house stairs, not too steep. There's a stairgate and a cot if you need them.
You can bring up to two dogs. The back garden is secure for them.
The village has what you need. A couple of pubs that do food, a small shop, some cafes. Everything is a few minutes' walk. There's a play area for children by the river.
For things to do, you're in the Wye Valley. Good walking straight from the door. You can walk up to the Devil's Pulpit for a view over the Abbey. Chepstow Castle is about ten minutes' drive. For a longer trip, the Brecon Beacons are maybe 40 minutes. The Forest of Dean is on the other side of the river, about 15 minutes away. They've got bike hire, a steam railway, and that sort of thing.
Useful links: Cadw for the castles and Tintern Abbey itself, and Wye Valley Area of Outstanding Natural Beauty.