Park Mountains

Upper Kings Creek Meadow provides an outstanding view of Reading Peak to the northeast, seen below. Reading Peak is a "plug" or dome-type volcano made up of stiff dacite lava. At one time it was called "White Mountain."

Reading Peak is as much a ridge as an actual peak. Like Lassen Peak, it composed of dacite lava. Once known as White Mountain, the mountain was named after Major Pierson B. Reading, a Lassen area pioneer. Reading led the third recorded ascent of Lassen Peak, and also filed a mining claim with Kendall Bumpass on the Bumpass Hell geothermal area.

Reading Peak accumulates a great deal of snow each winter, some of which remains on the northern side of the mountain into the summer months. This is even more visible from the Devastated Area, and from Hat Lake, which can be seen below. This picture was taken in October.

Remains of Mt. Tehama Long before Lassen Peak came into existence a much larger volcano was found in the southwest portion of what is now Lassen Volcanic National Park. It existed slightly south of the current location of Lassen Peak. This mountain, a stratovolcano, is now known as Mt. Tehama. Mt. Tehama arose some 600,000 years ago, and reached its full height 300,000 years ago. At full size this mountain was 15 miles in diameter and reached an altitude of 11,000 feet, far above the surrounding area.

At one time some believed that Mt. Tehama collapsed, but this is unlikely. It is now generally accepted that Tehama was largely destroyed by glacial erosion. Some remnants of the mountain can still be found in the park, including Brokeoff Mountain, Pilot Pinnacles, Mt. Diller, and several others, some of which are shown below. Lassen Peak itself rose on the northern slope of what was left of Mt. Tehama.

Bumpass Mountain, at 8760 feet, is located directly north of Bumpass Hell.

Diamond Peak is part of the central core of the ancient volcano. The "peak" is composed of an accumulation of erosion resistant volcanic rock. The derivation of the mountain's name is not certain, but may be based on the quartz and calcite crystals contained in the rock. Diamond Peak occupies what was once the central portion of Mt. Tehama.

Mt. Conard is located in the southwestern section of the park, just north of the park's southern border. It is a remnant of the east flank of Mt. Tehama.

The lofty and rugged peak known as Pilot Pinnacles is part or the northern rim of the ancient Mt. Tehama. Located on Brokeoff Ridge, it reaches an altitude of 8886 feet.

The second highest peak in the park is Brokeoff Mountain. It was part of the western flank of Mt. Tehama, and is the tallest remaining part of that mountain. It is the most prominent remnant of Mt. Tehama in the park. Its name is derived from its appearance; the mountain looks like a portion of it "broke off" from the rest. In fact, the shape of the mountain was determined by the erosive effects of glaciers. A map drawn by William B. Ide and Peter Lassen in 1844 labeled Brokeoff and Lassen as "Sister Buttes."