Giant Nail in the Wall.

Having problems with adding this!!!

My daughter picked me up from work today.
After a bit of shopping we went to the Car Park to get the car, where I found this & other giant nails.
I wonder why they're there & how long they've been there.

Sorry if I don't comment alot on your blips, I'm having to borrow this Lap Top to add things as mine is kaput.