Olentangy Indian Caverns

This is one of the more unexpected things to do near Delaware — a genuine limestone cave system just outside town, formed over thousands of years and used historically by Wyandot people, with guided tours that walk you through the passages and formations while sharing that history. Tours run roughly 45 minutes and are family-friendly, with a walkway system that makes it accessible without technical caving experience. The temperature underground stays cool and consistent year-round, which makes it a genuinely great option on a hot Ohio summer day or an unexpectedly rainy one. Above ground, the property also has a small pioneer village, gemstone mining activity, and gift shop if you want to extend the visit. It’s a fun, slightly offbeat stop that tends to surprise guests who weren’t expecting caves in central Ohio — kids especially tend to love it. Plan for an hour to ninety minutes total including the grounds. Comfortable shoes are worth wearing since some sections have uneven footing. A great option to break up a weekend of restaurant-and-park activities with something a little different, and an easy add-on to a Delaware day.