The Big Obsidian Flow on Paulina Peak is one of the highlights of the Newberry National Volcanic Monument. At only 1,300 years old, it is the youngest lava flow in Oregon. The flow overs approximately 1 square mile within the Newberry Caldera, the Paulina and East Lakes containing crater which formed with the volcano’s cone collapsed 75,000 years ago. While not part of that huge eruption, the Big Obsidian Flow was the final stages of another, large eruption occurring in 640 AD when magma containing very little gas oozed its was to the surface and cooled while it flowed down the mountain’s flank, creating the volcanic glass.
The trail begins from the Big Obsidian Flow trailhead on the south side of the main road within the monument, between Paulina and East Lakes. The parking lot is large and the trail heads out of the south side. The trail begins paved as it winds through the trees, but you will quickly find yourself at the base of a massive wall of obsidian and pumice.
To get up onto the flow, take a series of metal staircases as they weave their way up the lava. Once up, the trail turns into a rocky, natural surface as it travels along a nice loop through the flow. There are several interpretive signs along the way as well as stunning views of Pauline Lake and Peak. Also catch glimpses of life trying to find a way to recapture the lava, as flowers and small trees cling to life among the rocks. Once the loop is complete, head back down the stairs and marvel at the marvel you were just able to experience.
The reach the Little Crater Trailhead, head towards the turnoff for the Newberry Caldera on Highway 97, 6 miles north of La Pine or 17 miles south of Bend. Head East on the Paulina Lake Road. Continue up the road towards Paulina and East Lakes for 19 miles. Continue past the guard station and Paulina Lake and watch for signs directing you to the trailhead on your right.
Passes: A Northwest Forest Pass is required.
Dogs: Dogs are technically allowed and must be on a leash, but it is highly advised to leave Maramaduke at home for this one. The lava surface of the trail can be extremely sharp and hot in the summer and your pups feet aren't going to like it. And you aren't going to like carrying them when the refuse to go any further.
Open Season: The road up to Paulina Lake closes in the winter at 10-mile Snopark, 10 miles from the highway. It usually opens for the season in late May and closes in Mid Novemeber.
Bugs: Mosquitos will likey be present and persistent from late May into August or so.