Same here. I grew up in Newhaven in the late 70s/early 80s. I was always out on my bike, exploring and playing in woods, on the beach, the piers, the fort before it was renovated etc.
The kids were 8, 10 and 11. Is it reasonable to allow them out unsupervised? Genuine question. Let us know where you’re going, call if you need us, be sensible, be back by x o’clock?