High on the scrubby flanks above Old Stage Road, the Cave Boulder sits quietly against the hillside, waiting for climbers who crave tough moves and clean mountain air rather than the hustle of bigger crowds. At 8,399 feet above sea level, every breath is cool and thin — your senses sharpen as the trail pulls you along the base of a ragged cliff band, where the pine needles crunch underfoot and the distant cityscape gives way to exposed, rugged terrain.

The approach is just enough to keep things interesting: follow the cliff, and after threading a rope up a tricky section, keep your eyes peeled to the right. About 25 to 50 yards after the rope, the Cave Boulder emerges, its chalky faces cut by proud lines and angular overhangs. Here, in the pine shade, you’ll find four distinct boulder problems that combine challenging movement, creative solutions, and satisfying landings — all anchored by high-quality granite and an alpine vibe.

The area’s reputation is built around its classic climbs. "Optical Delusion" (V4, 4.5 stars) captures the heart of Cave Boulder climbers with unique holds that demand creative body positioning and unwavering commitment. For those looking for something next-level, "Union of Opposites" (V9) throws down powerful sequences — strength, precision, and problem-solving equally required. There’s aggression and possibility in the air here: "Optical Inclusion" (V5) and the open project "Optical Delusion Sit" (V11) round out this compact circuit, beckoning experienced boulderers to test their limits.

Each problem offers something unique. The grades are honest without being sandbagged — if anything, you’ll notice that the ratings reflect the technical demands rather than height or reach, much like the rest of Colorado’s granite bouldering. There's nothing overly soft about these grades: expect your efforts to be rewarded, but only if you bring grit and precision.

Planning a session here requires a bit of forethought. The elevation means weather swings come quickly; sunny mornings can shift to afternoon hail with little warning. The boulder itself stays shaded for much of the day, which is perfect for keeping friction high even on summer afternoons, but early and late season visits can be brisk. Pads are essential, as some landings are uneven, and careful spotting is a must — the approaches are rocky, and even strong ankles can suffer on a sloppy fall. For the approach, sturdy shoes and perhaps a short rope or handline add confidence on the technical section you’ll pass on your way in.

The Cave Boulder isn’t about numbers or endless problems — it’s about focus, style, and the satisfaction of solving intricate moves against a backdrop of Colorado’s craggy hillsides. After a strong session, you can linger a moment beneath the cliff band, city views falling away behind you, already making plans for another go at that elusive next grade. For boulderers chasing creative lines, alpine air, and the quiet reward of high-elevation exploration, this is a spot that lingers in the memory.