What background used in these promo render?

bsheers2003

I've seen this fantasy door background used elsewhere but cannot find the product for it yet.   Anyone recognize it?

attached is just one product in which it is used, King of Hearts Textures:

 

Rosie D

It is in  'A Curious Retreat'  - https://www.daz3d.com/a-curious-retreat

I use it a lot - it is set up as a portal