Top things to do

Top Choice Landmark in Mauna Kea

Mauna Kea's Summit Area

At 13,796ft in the air, you are above 40% of the atmosphere and 90% of its water vapor – apparently perfect conditions for growing the giant mushroom-like observatories that have popped up around the summit. Glisten…
Top Choice Archaeological Site in Mauna Kea

Lake Waiʻau

On an island with a conspicuous dearth of surface water, tiny Lake Waiʻau's existence on a porous lava mountain is something of an enigma. Hawaiian legends say it's bottomless, connecting the realm of the heavens an…
Historic Site in Mauna Kea

Mauna Kea Adz Quarry

Quarries scattered over 7.5 sq miles produced tons of exceptionally dense and fine-grained basalt (dubbed Hawaiʻiite) used to make a tool similar to an ax called an adz. The scale of the operation is difficult to ap…
Observatory in Mauna Kea

Subaru Telescope

When it came online in 1999, Japan's 8.2m (29.6ft) Subaru Telescope was the most expensive observatory ever constructed. The 22-ton mirror is one of the largest optical mirrors in existence. The telescope recently h…
Observatory in Mauna Kea

WM Keck Observatory

Mirrors larger than 8m (26.2ft) are so heavy that gravity distorts them as they move. Keck's breakthrough design overcame that limitation in 1993 by using a series of 36 hexagonal mirror segments mounted and indepen…
Sports in Saddle Road

Mauna Kea Polo Club

And now for something completely different: polo! An ancient game involving a ball, mallets and ponies played on an impressive, large field. The games are sponsored by Mauna Kea Polo Club and held 6.4 miles up Old S…
Park in Saddle Road

Mauna Kea Recreation Area

Desperately needed renovations have made the only public facilities along Saddle Road an altogether pleasant stop. Clean restrooms and a playground with plenty of ropes to climb mean it's an excellent spot to stretc…
Observatory in Saddle Road

Mauna Loa Observatory

The weather measurements made here are so sensitive that when the observatory was built in 1956 scientists asked the national park to ban stoves at the summit cabin, fearing those emissions 6 miles away would throw …
Observatory in Mauna Kea

Thirty Meter Telescope (planned)

Walk behind the Keck Twins and look northwest and you'll see...nothing. Down there is the ideal location for the TMT, which supersizes Keck's many-small-mirrors design to create the world's most advanced and powerfu…
Observatory in Mauna Kea

Submillimeter Array

These eight 6m (19.7ft) radio telescopes work together (via supercomputer) to create image resolutions equal to an antenna 0.3 miles in diameter. The SMA detects millimeter and sub-millimeter radiation, allowing sci…