Super gorgeous waterfront park just underneath the High Bridge (not to be confused with High Bridge Park across in Manhattan) along the Harlem River. Work has begun in repairing the paths along the River Towers apartments to the north so it will be even better.
Although I think it's super gorgeous, I can't give it beyond 3 stars because it is a nightmare to get to especially on bike. It's actually quite hazardous with no real direct safe route and if you're a brave soul you'll bike along the Major Deegan Service Road but that's not recommended due to high traffic. Once you do make it to the park it's so serene with the exception of the occasional Metro North train zooming by. They need more work in improving access but the views are gorgeous.