I agree one of the easiest trails at the Preserve is overcliff/undercliff. Trapps Road is also a relatively flat, easy trail. The trail around the lake and the trail to the tower are not part of Preserve Property. They are both on Mohonk Mtn. House Property. You can hike the trails at the Mtn. House via the Preserve trails. I wouldn't consider them difficult but they involve a few miles to get to them.
I would agree, it is mostly flat, with a few slight inclines. You can get a ride to the tower on the hill where the view is incredible, you can see 360 degrees and see several states.
Overcliff / Undercliff -- flat, scenic and relatively short
There's a really short flat trail around the lake at the hotel. Its pretty and very easy. My wife snowshoe'd it at 7months pregnant.
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