I wanted to leave an "Italian" memory for the participants, almost all of whom came from abroad, so I chose some famous monuments and created a container to fit them together.
As always in this type of puzzle, the pieces should not protrude or overlap. It's probably not very easy to solve. As far as I know, no one has found the solution yet.
Please note that I'm leaving for vacation. You can buy it, but I will ship in the second half of August.