A door through a dry stone wall.
When you come up against a stone wall, you don't have to give up.
If it is a dry stone wall you can always make a door and go through it.
If there is someone on the other side helping to make that opening, there is a collaboration.
An opening, unlike a collaboration, gets bigger the more you take away from it.
But both get easier as they get bigger.
It may take time to move all the rocks and you will need to watch out you don't drop any on the one you are collaborating with,
but in the end a 'way' can be made.
And the wall will not been be destroyed. In fact, it will be improved.