We walked the small loop on the boardwalk and didn't go to the falls. The sapphire pool is beautiful and we got some great pictures at this spot. There are several benches to sit and admire the view here.

The Mystic Falls trail down to the base of the falls is my favorite trail in Yellowstone and the Sapphire Pool is my favorite pool in all of Yellowstone and both are in Biscuit Basin. The trail is not difficult, but once you are at the end of the trail, you have the option of climbing down into the river and the falls. You can go from rock to rock to get down there. One of the hot springs flows into the river so you can stand in the steamy area where the hot water meets the cold. If you’re brave, you can make your way all the way to under the actual waterfall by carefully maneuvering from rock to rock. At least we were able to in July. (The height of the water in the river may be different in different months, but we were able to find rocks to step on that kept the water midcalf deep.) Be sure to wear shorts (so your pants don’t get wet) and river sandals with grips like Tevas etc so you don’t slip off the rocks. We spent over an hour exploring down there. It’s so beautiful and you get an intimate experience because most people don’t venture down into the falls. They stop at the view where the trail ends.

While in Yellowstone Park take the time to visit Biscuit Basin it is well worth it. With wooden walkways around the poo!s and geysers you can get close to these fascinating geologic features.