The Grotto

We returned to Cragside today with the intention of driving the Carriage Drive, but it was closed (again) this time for re-tarmacking.
After eating our packed lunch in the car in the carpark, we decided to return home but on the way out we noticed a road signposted to The Formal Garden. We had never been to this part of Cragside before so decided to explore. We met a couple leaving just as we arrived at our destination.
It was a beautiful garden with a hide in the car park where we watched a variety of different tits chomping on the peanuts put out for them.
This grotto was in the Formal Garden through a door that looked private - imagine our surprise to be greeted by this?