Onomea Bay Trail – Short and fabulous

If you travel north of Hilo (on the Big Island) for about 5 miles on the belt road (Route 19) you will see a sign directing you to a “Scenic Route” that forks off to the right. This is a section of the Old Mamalahoa Road that travels about 4 miles through some of the nicest rain forest scenery on the Island. It is one of our favorite side trips when entertaining Island visitors and occupies a permanent spot on our sightseeing agenda. You will see many photos taken along this road in the Hilo Gallery.

A major attraction on this route, deservedly so, is the Hawaiian Tropical Bioreserve and Garden. It is a wonderfully maintained and well-documented botanical garden filled with trees and plants that you may not see elsewhere. This garden looks out over beautiful Onomea Bay, a crescent-shaped bay with several islands that is somewhat protected from the north by a large peninsula:

Peninsula on north side of Onomea Bay. Almost an island!

The Onomea Bay trail is much less well-known than the Bioreserve and interestingly, the trail loops around and actually through the Bioreserve. The trail is free and has a well-marked trailhead a bit south of the Bioreserve. It descends towards the bay, providing gorgeous cliffside views of the bay:

A view from the Onomea Bay trail. You can walk out on the peninsula seen here when the water is not too rough

The first section of the trail is paved, short, and easy to walk. If you do nothing else here, make this walk. But if you continue, you will come to the Bioreserve, which is fenced off on either side of the Onomea Trail. Bioreserve visitors can pass across the trail to explore both sections of the gardens. Friendly security personnel monitor these crossings. If you are walking the Onomea trail, you have two choices at this point. A path adjacent to the Bioreserve forks off to the right (before the Bioreserve) and goes down to a tree-lined and rocky shore, where there is sometimes quite a crashing surf show:

Rough day on Onomea Bay. Not safe to walk out to the point

Trees come right to the waterline in this little cove. Great jungle feel!

t's a marvelous and jungle-like spot. When it’s calm enough you can walk out on a short peninsula and watch the surf up close. If nothing else, it’s a great photo-op for you and your friends:

Safe for my daring trekking partner to be out on the point.

After taking this side trip, you will head back to the main trail and can continue past the Bioreserve trail crossing down the trail to the shoreline. After the Bioreserve crossing, the paving ends and the trail can become much more muddy if there has been recent rain. Be warned (!) and make sure you have appropriate shoes. Often, some good souls throw down palm fronds to make it safer and cleaner to get through the muddy parts.

When you reach the shore, you will be standing on a tiny inlet. To your left is a very serene pool with a pair of small cascades pouring into it from within the Bioreserve.

Cascade flowing into Onomea Bay

To the right, you can look out into Onomea Bay and see the “Twin Rocks” just offshore:

The Twin Rocks of Onomea Bay

There is a Hawaiian legend about these rocks involving young lovers that you can read about in many places, such as here.

Usually a small current flows in and out of the inlet that is easily crossed if you don’t mind some wet feet. The reward for doing so is access to another short peninsula that extends along the main body of the bay. There are beautiful views from this peninsula, such as these:

Looking north across Onomea Bay from the trail

The inlet, as seen from the peninsula

The Twin Rocks and coastline north of Hilo from the Onomea Bay trail

At this point, we usually turn around and return to our parking place on the road. If you are in a hurry, this whole route can be seen in about 30 minutes (much less if you stop at the Bioreserve crossing), but I recommend a more leisurely trek, exploring as you go.

If you decide not to turn around, you can continue on the trail around a portion of the main bay. This soon enters private land, so mind the signs. The main trail itself heads uphill, through the woods and back to the main road. This section of the trail is a bit more rugged, steeper, and has few views. If you choose to take it, you will arrive on the main road on the north side of the Bioreserve, having now passed around and through it. There is parking here for those who want to walk the trail in the opposite direction.

The trail is a gem, not to be missed if you are on the Scenic Route. But this trail does not replace a visit to the Bioreserve, so stop there too if you have the time.