1. We got so lost that we ended up going around Robin Hood's barn to get to Tom and Diane's new house.
2. It seems your mother can't read a map—her directions took us all around Robin Hood's barn!

Reference to Robin Hood, the legendary outlaw, whose barn was simply the fields and pastures surrounding Sherwood forest, his home. “Around Robin Hood’s barn” simply means all around the countryside, all through the fields and pastures.