The Twin Sisters Trailhead perches in thick lodgepole pine forest 0.4 mile up an unpaved road from the left side of the parking lot across CO 7 from Lily Lake. Using switchbacks, the trail maintains a reasonably gentle grade for about 3.0 miles to tree line. Hikers who are climbing Twin Sisters to condition themselves for higher climbs may become winded, but they can hide this fact by claiming to stop to enjoy the fine views of Longs Peak across the Tahosa Valley.
Above tree line, more switchbacks lead to a rocky tundra meadow between two summits of Twin Sisters. The lower western summit attracts the most visitation. A trail still leads to the site of a fire lookout that stood here until 1977, when the NPS removed it because it was no longer necessary for wildfire control. The view remains as ample testimony to why the lookout stood on this spot. A stone hut housing a radio repeater used by various government agencies sits below the western summit. The eastern summit, 15 feet higher, provides good views of the foothills of the Rockies and the megalopolis spreading between Colorado Springs and Fort Collins.
Lodgepole pines along the lower part of the Twin Sisters Trail grow there because fire destroyed denser forest and created room for sun-loving lodgepoles. Similarly, in 1929 a fire destroyed a stand of lodgepoles on the west flank of the peaks, allowing quaking aspens to replace the pines. The stand of aspens is called the Butterfly Burn. The supposed butterfly shape is rather vague, but the butterfly colors appear beautifully above the Tahosa Valley in September, when these trees are among the first in the area to turn red and yellow.
About 2.7 miles from the trailhead, at the top of a low point on the ridge north of the summits, some maps show a feature called Lookout Springs about 0.25 mile east of the trail. This spring was once a drinking water source, but I doubt its purity and recommend that you skip sampling it and instead carry your own water.
To help fight the heat of a summer day, you may want to put a three-quarters-full water bottle in the freezer the evening before your hike. It will contain a lump of ice when transferred to your pack. Carried next to your back, the ice will absorb heat generated by hiking and melt into cold drinking water. Thus the bottle will cool you on the outside as well as the inside.
A better solution is to climb Twin Sisters not on a hot summer day but on a cool summer night. The trail is clear enough to hike by starlight, and a full moon is magic if you can arrange it. A flashlight is worth its weight in confidence.
Starting well before dawn (camping is forbidden on Twin Sisters), you should arrive on the ridgetop in time to witness sunrise above the plains, shining with reservoirs. Photos should include silhouettes of some limber pines in the foreground.
Few early-morning hikers who arrive on top of Twin Sisters, 3.9 miles from the trailhead, are eager to leave; they literally have all day. Yet there is much to experience on the easy return. Pikas squeak their alarm from the invisibility of their near-perfect camouflage among the rocks. Also finding shelter among the rocks is dwarf blue columbine. This rare alpine flower is only a few inches tall with stubby curved spurs, an obvious relative of the Colorado blue columbine, Colorado’s state flower. Additional interesting photos of limber pines present themselves on the way down.
The limber pines are dramatic in shape because of winter wind that blasts Twin Sisters. Winter hikers bold enough to face this bombardment (100 miles per hour is not unusual) at least will not be hampered by much snow, which the wind blows away. There is more snow below tree line in winter, but it often is so hard packed that snowshoes are not needed. The winter trail to Twin Sisters begins just above the parking lot across CO 7 from Lily Lake, adding 0.4 mile of walking on the closed unpaved road to the summer trailhead.