Secret Caverns is a bit less commercial than Howe Caverns (https://howecaverns.com), and includes a 100 ft. underground waterfall
Vroman's Nose in Middleburgh (about 40 min from Summit) - hike up a mountain with a view of the valley. At the bottom of the trail is a tiny, charming cafe called "Under the Nose". They have light lunches, homemade sweets, and locally crafted gifts. Really darn cute place to stop after a hike. Giant's Ledge near Phoenicia (about an hour from Summit) - then stop at the famous Phoenicia Diner or Woodstock Brewing for lunch Kaaterskill Falls in Hunter (about an hour from Summit) - views of one of the highest waterfalls in New York