Kelleys Island is just a couple of miles from Put-in-Bay, but couldn't be more different. PIB has a huge party scene, while KI is very laid-back. I've always camped at the state park on the north end of the island, which has nice showers and a sandy swimming beach. The "village" has a few bar/restaurant places, most with decent food. Nothing 5-star, but it's not that kind of island. Love to bicycle the island -- it's mostly flat with few cars, but lots of lake vistas and a few historic old buildings. If you don't bring a bike it's worth renting a golf cart and exploring the place. An hour or two should be sufficient.
It's not cheap to get out there, so not the best choice for a day-trip. Cell service is limited beyond the village area on the south side of the island -- so you have an excuse to (mostly) unplug and enjoy nature here.
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