Mauna Kea: Astronomers from around the world explore the universe from its summit and the Hawaiian people go to it in search of ancient spiritual connections. For visitors, it is one of the clearest places on the planet for viewing the night sky and offers a rare opportunity to experience the polar tundra in Hawaii.

When you were planning your Hawaii vacation, you might have been dreaming of tropical climates but how about a beach snorkel and a snowball fight in the same day?

It’s possible on the Big Island, which is home to 11 of the world’s 13 climates.

Mauna Kea the Research Site

Mauna Kea is a dormant volcano on the Big Island of Hawaiʻi that last erupted approximately 4000 years ago. At 13,796 feet above sea level and over 33,000 feet from the bottom of the ocean floor, Mauna Kea is the tallest sea mountain in the world.

Mauna Kea’s summit is home to the world’s largest observatory for optical, infrared and submillimeter astronomy. Research teams from eleven different countries operate 13 telescopes atop Mauna Kea.

Mauna Kea: Home of Poliʻahu

In Hawaiian mythology, Mauna Kea is home to the snow goddess Poli‘ahu. In ancient times, the summit was considered the realm of the gods and was kapu (forbidden) to all except the highest chiefs and priests.

Tips for Visiting Mauna Kea

Before you make the trek up the mountain, there are a few things you need to know. It’s recommended that children under 16, pregnant women, and those in poor health not go higher than the Onizuka Center for International Astronomy Visitor Information Station (VIS), at 9,200 feet.

Mauna Kea Visitor Information Station

The Visitor Information Station is an interesting stop in its own right — it’s the best amateur observation site on the globe, with a handful of telescopes for viewing. Visitors should note that the telescopes at the summit are for the astronomers only, but guests who make it that high can still enjoy the diamond-studded sky and see more stars than they’ve likely ever seen before. The Onizuka Center holds free nightly stargazing sessions here as well from 6 to 10 p.m.

Mauna Kea Summit Tours

On the weekends, the VIS offers escorted summit tours, heading up the mountain in a caravan. If you don’t want to make the drive yourself, opt for a handful of tours that will take you to and from the summit.

Weather

Know that Mauna Kea weather varies greatly and can change quickly. Daytime temperatures average between freezing and 45 degrees Fahrenheit. Summit winds above 120 mph are not uncommon, and there have even been snowstorms during the summer months. Not only that but at 14,000 feet, be prepared for 40 percent less oxygen than at sea level.

Altitude Sickness

Altitude sickness — including shortness of breath and impaired judgment — is a big possibility so proceed with caution, stop at the VIS for at least half an hour to acclimate, and don’t overexert yourself.

Snow Boarding in Hawaiʻi

A special note for extreme adventurers: You have to be in good shape, but snowboarding is possible in Hawaii. There are no lifts, so you must walk up the mountainside on foot, but Mauna Kea sees its fair share of brave boarders who are willing to make the effort.

You’ll even see a few locals carting home a truck bed full of snow so Keiki (children) can enjoy making a snowman in their front yards at sea level.

Be sure to check access to Mauna Kea prior to visiting.