Kaaterskill Falls, one of New York's most impressive waterfalls*, has been undergoing trail renovation over the past couple of years. There was no official trail past the base of the falls, yet people climbed up there regularly, and every year a couple of people fell to their death.
Since I was last there, a new trail has been built to the top - a very solid set of stone stairs. Eventually, there will be a viewing platform at the top, but when we were there, construction on a bridge over the falls prevented access in that direction. You can reach the top, but you can't see much from there.
Despite a dry summer, the falls were still running, but with less water than on my previous visit. It's still worth the steep hike up from the road (not to mention the crowds at the lower levels). What's still a huge pain is parking; the lot simply isn't big enough. People, this is not the place to leave generous space between your cars!
* Obviously, Niagara Falls is the most impressive.