Lion's Lair is an exceptional trail that was added to Boulder's Open Space and Mountain Parks (OSMP) system in 2015. Experience gentle switchbacks through the ponderosa forest and a steady grade with smooth surfaces. As you ascend, views of high peaks and rolling forests get better and better. This trail accesses the Mount Sanitas summit, which offers expansive views of Boulder. There are lots of species of wildlife along this corridor. Bring your birding binoculars and be aware of mountain lion activity. Dogs are prohibited.