Enjoy the Lake
Free public beaches include: Rendevous, State Park Marina, North Beach (reservations required), and several smaller but very nice beaches on the east side. Epic Recreation rents everything you could ever want, and we've had good customer service from them.
See more about beaches under "Tips for your Trip."
Explore a Cave
Minnetonka Cave is open daily in summer months and is a true hidden gem. Call for reservations. Take a jacket and be ready for some stairs.
Go biking
There is a great bike bath in Garden City, and they are working on extending it around the lake. There is also wonderful mountain biking to be had. Stump Hollow, Sink Hollow, Bunch Grass up to White Pine Lake, and Jardine Juniper are some of our favorite intermediate/advanced trails.
Try A Rope Swing
Bloomington Lake is a bit of a drive, but worth it. Drive 20 miles north to Bloomington, then it's a dirt road for 12 miles, then a short 10 minute hike. The lake is great for paddle boarding, and has a fantastically fun rope swing.