Entry No. 14 — the Boulder file — filed under: outdoor
Eldorado Springs Pool
Tucked into the mouth of Eldorado Canyon, this artesian-fed pool has been drawing swimmers since it opened on July 4, 1905 — originally billed as the largest swimming pool in the country. The water flows from a spring whose aquifer reaches 8,000 feet below the Continental Divide, arriving at the surface at a steady 76°F and tasting clean and mineral-bright. Sheer red-and-tan sandstone walls rise on both sides, making every lap feel like swimming inside a canyon. The resort's glory years drew 60,000 visitors a summer, along with Douglas Fairbanks and Jack Dempsey. Aerialist Ivy Baldwin walked a wire stretched 635 feet across the canyon — suspended 582 feet above the gorge — 86 times between 1907 and 1948, his last crossing on his 82nd birthday.
The story
You're swimming in water that spent time eight thousand feet beneath the Continental Divide before forcing its way up into Eldorado Canyon. When the Eldorado Springs Pool opened on July 4, 1905, resort promoters bragged it was the largest swimming pool in the United States. But the real draw wasn't just the acreage—it was the bizarre spectacle wedged into a mountain notch. Between 1907 and 1948, high-wire artist Ivy Baldwin strung a tightrope wire 635 feet across the canyon—suspended 582 feet directly above the gorge—and walked it 86 times, completing his final crossing on his 82nd birthday while bathers watched from the water half a thousand feet below.
In its mid-century heyday, 60,000 visitors a summer squeezed into the canyon mouth, including heavyweight boxer Jack Dempsey and silent film star Douglas Fairbanks. What remains today is an impossibly scenic bathhouse setup hemmed in by sheer red-and-tan sandstone cliffs that swallow half the afternoon sky. The artesian water arrives at the surface at a constant 76°F—crisp, mineral-bright, and clean without the nose-stinging chemical cloud of a municipal pool.
What it's like
Drive down Artesian Drive into the canyon notch or catch the weekend shuttle to bypass the parking gridlock. After signing the mandatory adult waiver and paying at the gate, claim a patch of concrete or rock deck beside the sandstone cliffs. The vibe is strictly throw-back retro: trail-dusted hikers washing off dirt, families with coolers, and locals doing laps under sheer rock walls. The 76°F water is brisk enough to make you gasp if you wade in slowly, so jump straight in. If you want to avoid the peak crowds, target the Monday-through-Thursday late-day slot after 4pm when the rocks drop into shadow and admission drops to $15.
The move: Pack a picnic and arrive early before the canyon fills with day-trippers. Swim in the cold artesian water, then dry off on the rocks while the sandstone walls glow in the afternoon light. The canyon setting does all the ambiance work — bring towels and leave your phones in the bag.
📍 Before you go Open Memorial Day weekend through Labor Day, daily 10am–6pm; weekends only in September. Adults $25, children/seniors $15; late-day rates (4–6pm Mon–Thu) drop to $15/$10. Parking is first-come, first-served and fills fast on weekends — a free Eldo Shuttle runs every 20 minutes on weekends and earns you $5 off admission. No reservations required; tickets at the gate or online. Adults must sign a waiver on arrival.
- 📍 Boulder
- 💸 $$
- ⚡ Low-key
- 🌗 Indoor or outdoor
Where: 294 Artesian Drive, Eldorado Springs, CO 80025
Hours: Added 2026-06-11 — confirm current hours before you go.
⚠ Seasonal or scheduled — always check before you go.
Pair it with
- Crags Hotel Ruins at Rattlesnake Gulch — Hike less than a mile up the canyon to explore the foundation ruins of a 1908 resort perched above the gorge before soaking off the trail dust in the spring pool.
- NCAR Mesa Laboratory — Drive three miles north to trade natural sandstone walls for I.M. Pei's dramatic 1967 brutalist lab built directly into the mesa edge.
- The Sink — Head five miles north into Boulder to dry off over burgers at this 1923 basement tavern covered in decades of graffiti.
Good to know
How cold is the pool water?
The pool is fed by an artesian spring coming from deep beneath the Continental Divide, arriving at a steady 76°F. It feels cool and refreshing rather than heated, so expect a cold shock when you dive in.
What are the seasonal operating hours?
The pool is open daily from 10am to 6pm from Memorial Day weekend through Labor Day, then runs on a weekends-only schedule through September.
How much does admission cost and do I need a reservation?
No reservations are required—tickets are sold at the gate or online. Standard entry is $25 for adults and $15 for children and seniors. Late-day passes (4–6pm, Monday through Thursday) drop to $15 for adults and $10 for kids/seniors. All adults must sign a waiver upon arrival.
What is the best way to handle parking?
Parking on Artesian Drive is first-come, first-served and fills early on summer weekends. Taking the free Eldo Shuttle on weekends drops you right at the entrance and gets you $5 off your pool entry.
Plan a visit & invite your people →
Further reading: Official site · aboutboulder.com · bouldercounty.gov
last checked: 2026-06-11