Hello. This link might be helpful.
Here is just what you are looking for: https://www.youtube.com/watch?v=TX9afxu0GfM&app=desktop
Hi Anna, hope this helps you build your small rock grotto. 60 Backyard grotto ideas | prayer garden, marian garden ...
www.pinterest.com › shanmay2102 › backyard-grotto-i...
tree altar for Mother Mary Blessed Mother Mary, Blessed Virgin Mary, Religious Icons, ... We would like to build a nice grotto (cave-like structure for it), that is not too big. ... 48 Simple Rock Garden Decor Ideas For Your Backyard - garden ...
Hi! If you want a shelter type, it used to be very common around here to bury an old tub and then use it as a form to attach materials to. I've seen some really nice ones! Good luck!
Hi Anne, this post might help... https://www.hunker.com/13404817/how-to-make-a-grotto
Hi Anne: I just read this, it may help:
You don’t need to be a stone mason just be creative, use stones that can be handled easily and randomly place them around where you will be placing the Statue. In the back of the statue you can pile some rocks to give it a cliff effect and try to place the statue on a flat stone to keep it off the ground. Leave large enough spaces between the stones to plant flowers or shrubs. Also if you can protect the the statue from the elements it will last longer.
Another person said that they used an old bathtub, buried it in the ground a bit and added rose bushes and shrubs to hide the fact that it's a tub.
You may use both ideas, securing rocks to the tub with mortar.
What a lovely idea. Any suggestions I would have are vague like make sure your rock size is in proportion to your statue and the color is consistent.
I hope this isn't against the rules but since you asked this question I thought you might enjoy this site. It is about an hour from my house and it is so cool.
You may also want to google the grotto and look at images. There aren't many on their site.