Okotoks Erratic Mountain
Largest glacial erratic in Alberta, notable boulder
A massive glacial erratic near Okotoks, Alberta-one of the largest of its kind in Canada. The site has short trails, interpretive signs and picnic spots.
Okotoks Erratic at a Glance#
Address: Located near the south bank of the Sheep River, just outside Okotoks, Alberta
Hours: Open 24 hours
Admission: Free
How to Get to Okotoks Erratic#
Drive south from Calgary along Highway 2 to the town of Okotoks (about 30-40 minutes). From Okotoks town centre follow local signage to the Big Rock site near the Sheep River on the town’s western edge; limited parking is available.
Tips for Visiting Okotoks Erratic#
- Go at first light-Big Rock is quiet then and the low sun brings out its textures
- Respect the site: do not climb the boulder; erosion and fissures make it unstable in places
- Read the interpretive panel on-site to learn about the glacial journey that brought the stone south
Best Time to Visit Okotoks Erratic#
Accessible year-round; spring and autumn offer the best light and fewer people.
Weather & Climate near Okotoks Erratic#
Okotoks Erratic's climate is classified as Warm-Summer Continental - Warm-Summer Continental climate with mild summers (peaking in July) and freezing winters (coldest in January). Temperatures range from -16°C to 23°C. Semi-arid with limited rainfall.
January
January is the coldest month with highs of -4°C and lows of -16°C. The driest month with just 15 mm.
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February
February is freezing with highs of -1°C and lows of -13°C. Light rainfall.
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March
March is freezing with highs of 4°C and lows of -9°C. Light rainfall.
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April
April is cold with highs of 11°C and lows of -3°C. Moderate rainfall (33 mm).
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May
May is cold with highs of 16°C and lows of 2°C. Moderate rainfall (59 mm).
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June
June is cool with highs of 20°C and lows of 6°C. The wettest month with heavy rain (102 mm).
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July
July is cool with highs of 23°C and lows of 8°C. Moderate rainfall (59 mm).
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August
August is cool with highs of 23°C and lows of 8°C. Moderate rainfall (57 mm).
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September
September is cool with highs of 18°C and lows of 3°C. Moderate rainfall (51 mm).
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October
October is cold with highs of 12°C and lows of -2°C. Light rainfall.
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November
November is freezing with highs of 3°C and lows of -10°C. Light rainfall.
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December
December is freezing with highs of -2°C and lows of -14°C. The driest month with just 15 mm.