Deer Run Ridge is located in Georgia. It is 1261.8 meters long with an average gradient of 21.5% and a maximum gradient of 42.8%. Find similar hills.
Within a gated community, this hill is a serious contender for steepest hill in the country. This blog post will give you all of the information I have on the climb. Unfortunately, it's within the private gated community of Big Canoe, which is probably how they got away with making a hill this ridiculous. Coincidentally, I have a cousin who lives there, after I wrote the above I was able to go there and actually give it a crack. I brought my climbing bike with a low gear of 26-36 and still had to stop several times. You know how you climb a hill like Mount Tom and when you get through the 20% section 12% starts to feel "easy"? Well, with this hill, replace the 12% with 20% and 20% with 30%. Completely insane, but worth every minute of it.