This was a great hike and something that I had looked forward to doing in anticipation of our trip to Yellowstone. We entered Toms Trail by parking in the first parking lot on South Rim Drive. The trail is very popular and therefore very crowded and Very Steep! I actually held onto the railing going down. It was scary. Going up I could concentrate on what's ahead and moved quickly. I see that my heart rate reached 147 which is not as high as some bike rides. Nonetheless I was somewhat winded though not thirsty. It was very warm and I handed off my green hoodie to Tess before continuing down on the stairs. When I got back to the top we were both so excited that we forgot all about the jacket. The temp variation in the course of the day is amazing. Families were on the stairs and some kids were running up like it was nothing while many others were taking rest stops as well as pictures. I would compare the stairs to Triple Falls in DuPont but metal, steeper and longer. The whole experience was awe inspiring!