Start at the northeast gate of the Yellowstone National Park (YNP). Any gate will do but from the gate get to US 212. US 212 runs a long the north part of YNP in a east west direction. From the northeast gate go past Soda Butte down the canyon to the Lamar Ranger Research Station and stop at the small turn-out on the south side of US 212 about a half mile from the station. For others coming from a different gate get the free YNP map and find the Lamar Ranger Research Station on Us 212. Park at the turn-out and being careful of the animals (read the rules about maintaining distances to the different animals) walk towards the grove of cottonwoods to the south and slightly east of the turn-out. Walking sticks come in handy as you cross water twice. I never got my shoes wet. When you arrive at the trees look west to the tree in the middle it splits into two trunks. Look at the bottom and find the hollow.