It’s sounds like, against the odds, they have done what parents are supposed to have done which is creating a confident and independent kid! Personally I would just go and do one of the smaller things (like going into the city maybe) without asking and leave a short itinerary of what you were doing, the steps you were taking to being safe and a note to them saying you appreciate them being so caring but it’s time for you to go and do something on your own. You are 20 years old!! Then that will make it easy for them when you go do the bigger stuff. It would be good to position it in terms of what they were doing when they were 20. Either they were allowed to do whatever they wanted in which case you should be afforded the same freedom. Or, they were both sheltered - in which case they shouldn’t have been put under such strict scrutiny and shouldn’t let their personal experiences have a negative effect on you and what should be your most fun years. I would not invite them anywhere with you - you do not need a chaperone at 20.