What's the longest your horse has gone without being ridden and how did it act?

A couple years ago I jumped on my moms old mare bareback (that hadn't been ridden in nearly 16yrs) and was awesome! I swung up on her bareback with nothing on, and I walked her around a bit and she was perfectly fine. My mom was like WOW you JUST did that lol. I thought it was pretty cool. Other then that most of the horses get 4-5 months off depend on when spring decides to come around and the ground thaws. They are on the most part VERY fresh....for the first 2 weeks they all usually get lunged for 20 minutes as it can get pretty exciting if I don't.....such as JJ spooking at the dog that he sees EVERYDAY and thinking it was going to eat him.....he also spooked at a bush. BB spooked at a log that he lived with that past summer lol, and lots of other silly monsters are found.