Kendall Cliffs is a great place to spend some time rock climbing, whether you've never done it before or you're a seasoned pro. The options are bouldering with a mat, climbing with someone to belay you that doesn't work at the gym, or climbing with someone to belay you that does work at the gym. The latter requires a reservation and $20 per person, making it the most expensive option. You can rent your shoes and harness there. The walls are great; they range from beginner to advanced. There is a bouldering "cave" and an arch for the most experienced. Overall, if you want to go rock climbing and live within about 20 minutes of Peninsula, Kendall Cliffs is worth your time.