This small spur trail can be accessed from the Taconic Crest Trail, from either Route 2 or Route 346. I'd recommend getting to this trail from the Route 2 parking as opposed to the Route 346 parking area.
The snow hole is a small cave that you can descend into, that (usually) has snow in it year-round. When I went in early July, there was nothing but a snowball left. This is a nice area to cool off before re-entering the sweltering summer heat.