Spruce Mountain is located in New York. It is 2905.6 meters long with an average gradient of 10.8% and a maximum gradient of 20.2%. Find similar hills.
I found this one browsing in terrain mode. The road climbs to a fire tower, and from the bottom you can tell it's steep. The condition, however, is not suitable for a road bike, so I didn't attempt it. It is also technically closed to the public, but I spoke with someone who lived near the bottom who said it would generally not be a problem to ride a bike up there.