Unable to answer "What kind of parking is this?" – Parking Lot – https://osm.org/way/543726598 via StreetComplete 58.2:

I believe this car park is for blue badge holders only and requires prior booking. The road is closed to "unauthorised" vehicles. Check if it's possible to capture it with OSM tags. National Trust visitors should use Needles  car park where they're currently getting a discount.