Mt.Rainier is considered to have three seperate summit peaks;Columbia Crest is the highest at 4392m (14,410ft), Point Success 14,158 ft (4315m) and Liberty Cap 14,112ft (4301m).
The Geology Bit
It has formed due to the subduction of the Juan da Fuca plate beneath the North American plate forming the Cascade Volcanic Range. Fluids from the subducted oceanic plate have caused melting of the the mantle wedge above the plate and this melt or magma has then risen to the surface and erupted gradually forming the cone of the volcano. It last erupted in 1894 and there are still active fumaroles at the summit which help keep the top free of ice and snow.
USGS Current Activity Update
What to see and How to see it?
At over 4000m high Rainier reaching the summit is not a casual stroll in flip flops! Only half of summit attempts are successful and the ascent requires specialist equipment and experience from the climber or their guide. Having said this 5000 people climb Rainier a year over 2-3 days . Most attempts start from camp Muir on the south western side. Failure is often due to poor weather and fitness.
Rainier Mountaineering Inc.(Guided climbing of Rainier)Mt.Rainier National Park Climbing Guidelines
Alpine Ascents (Guided climbing of Rainier)
Mt.Rainierblogspot (lots of info on route conditions, permits etc.)
Henry M. Jackson Visitor Centre and the Paradise sub-alpine meadows are the main destination. A new visitor centre will open in 2008 along with a refurbished Rainier lodge. The Wonderland trail is a 90 mile backpacking trail which circles Rainier and for which you must book a permit. Day walks at Paradise are beautiful with good views of the glaciers on Rainier. There are over 200 miles of trails. In Sunrise area 6400feet you can drive to 6400 ft and take the mountain trails.
Look out for bears and although its lovely to have peace and quiet - if you sit quiet and still for too long you might have company.
Flooding in November 2006 closed the park when 18 inches or rain fell in 36 hours . Some trails are still being repaired so check before you set out if your route is open. Paradise is regarded as one of the snowiest places in the world. In 1971-2 28m of snow fell during the winter.
(Figure 2.4) could provide the largest sources of material for future lahars. Consequently, rivers heading on the west and northwest sides of the volcano are particularly vulnerable to large debris avalanches and lahars. These include the Puyallup and Carbon rivers, which drain into Puget Sound through the densely populated Seattle-Tacoma metropolitan area (Figure 2.1). Debris avalanches of large volume are most likely to occur during eruptions, but they could also occur during dormant periods (Crandell, 1971; Frank, 1985; Scott and others, 1992).
All the major rivers that drain Mount Rainier, except the Puyallup-Carbon system, are dammed at distances of 40 to 80 km downvalley from the summit (Figure 2.1). If reservoirs were empty or nearly so, these dams could probably contain all but the very largest expectable lahars and floods. However, if the reservoirs were full or nearly so, lahars could cause overtopping of the dams and significant downstream flooding.
Damage to property and loss of life from debris flows could be substantial. Geologic mapping of surficial deposits in Mount Rainier National Park by Crandell (1969), and later investigations by Scott and others (1992), have shown that numerous debris flows have entered the Puyallup, Nisqually, and White rivers in the past several thousand years. The largest debris flow from Mount Rainier, the Osceola Mudflow, occurred about 4,500 to 5,000 years ago (Scott and others, 1992; see Table 2.1). This mudflow traveled down the White River drainage system a distance of approximately 110 km, transported at least 3 km3 of rock debris (Scott and others, 1992), and buried parts of the Puget Lowland that are now heavily populated (see Figures 2.5 and 2.6(A)). For comparison, the devastating debris flows of the 1985 eruption of Nevado del Ruiz that killed 25,000 people had a volume of 0.048 km3 (Lowe and others, 1986), only about 2.4 percent of the volume of the Osceola Mudflow.
Another major lahar, the Electron Mudflow, swept down the Puyallup River Valley (see Figure 2.5) about 550 years ago. Recent excavations in this mudflow for construction in the town of Orting, about 50 km from the volcanic edifice, uncovered 2-m diameter Douglas fir stumps