Lake Erie, but Presque Isle might be more special. I'd do Vermilion on a random boring Tuesday you need to get out a bit.
If you have any reason to combine Vermilion with anywhere between Avon and Sandusky, then it's a different story. It's worth combining with something, but not a complete destination, if that makes sense.
(Merry Go Round museum in Sandusky maybe? Trying to think of something besides Cedar Point! The beach in Huron too?)
There is a lighthouse, and there *was* a museum--not sure if it's still open (I vaguely remember something about it being bought in 2016 or so and a controversy about what they were going to do with it).
I was last there in 2022 to see my friend, and it was hard to find parking on a summer weekend. I think that may have always been the case, but it's different when it's your parents looking for parking as a kid and you doing it as an adult :)
