The rim encircling Crater Lake,
when seen from a distance from any side, appears as a broad cluster of gently
sloping peaks rising about 1,000 feet above the general crest of the range on
which they stand. A good view is obtained from the road along Anna Creek, where
the southern portion of the rim appears as shown on Pl. III, B. Here
Castle Crest and Vidae Peak are the most prominent features, with the canyon of
Anna Creek in the foreground. The topographic prominence of Mount Mazama can be
more fully realized when it is considered that it is close to the head of Rogue,
Klamath, and Umpqua rivers. These are the only large streams breaking through
the mountains to the sea between the Columbia and the Sacramento, and their
watershed might be expected to be the principal peak of the Cascade Range.
Plate III.—B. RIM OF CRATER LAKE ACROSS CANYON OF ANNA CREEK
In the foreground is the canyon of Anna Creek; in the background Castle Crest is
seen on the left and Vidae Peak on the right.
To one arriving by the road at
the crest of the rim, the lake in all its majestic beauty (Pl. IV) appears
suddenly upon the scene, and is profoundly impressive. The eye beholds 20 miles
of unbroken cliffs, the remnant of Mount Mazama, ranging from over 500 to nearly
2,000 feet in height, encircling a deep, blue sheet of placid water in which the
mirrored walls vie with the original slopes in brilliancy and greatly enhance
the depth of the prospect. The lake is about 4-1/4 miles wide and 6-1/4 miles
long, with an area of nearly 20-1/2 square miles.
Plate IV.—PANORAMIC VIEW OF CRATER LAKE.
(click on image for an enlargement in a new window)
From the wooded slope a short
distance within the rim at Victor Rock, an excellent general view of the lake
may be obtained. The first point to catch the eye is Wizard Island, lying nearly
2 miles away, near the western margin of the lake. Its irregular western edge
and the steep but symmetrical truncated cone in the eastern portion are very
suggestive of volcanic origin. We can not, however, indulge our first impulse to
go at once to the island, for the various features of the rim are of greater
importance in unraveling the earlier stages of its geological history.
On the left is the western
border of the lake shown in Pl. IV, with the Watchman, Glacier Peak, and Devils
Backbone opposite Wizard Island, and Llao Rock beyond. These features, with
Victor Rock in the foreground instead of the Watchman, are much more clearly
shown in Pl. V, from an excellent photograph by Mr. Cunningham. On the right is
the southern border of the lake. Castle Crest, Kerr Notch, Scott Peak, Sentinel
Rock, and Cloud Cap appear in the distance along the rim. The boldest part of
the southern rim is cut off from this view by Castle Crest. A more complete
general idea of Crater Lake and its surroundings may be obtained from the map,
Pl. VI. The broad, gentle outer slope, with an inclination ranging from 10° to
15°, is in strong contrast with the abrupt inner slope, with its many cliffs.
This difference is well expressed by the relative position of the contours in
the map. The vertical interval of the contours is 100 feet. On the inner slope
the contours are crowded close together to show an incline so steep that one
needs to travel but a short way to descend 100 feet, while on the outer slope
the contours are so far apart that one needs to travel a considerable portion of
a mile to descend the same distance. The outer slope at all points is away from
the lake; and as the rim rises at least a thousand feet above the general level
of the crest of the range it is evidently the basal portion of a great hollow
cone in which the lake is contained.
Plate V—WESTERN BORDER OF CRATER LAKE FROM VICTOR ROCK TO LLAO ROCK.
In addition to the strong
contrast between the outer and inner slopes of the rim the map shows the
occurrence of a number of small cones on the outer slope of the great cone.
These adnate cones have peculiar significance when we come to consider the
volcanic rocks of which the region is composed. The rim is ribbed by ridges and
spurs radiating from the lake, and the head of each spur is marked by a
prominence on the crest of the rim. The variation in the altitude of the rim
crest is 1,460 feet, with seven points rising above 8,000 feet. The crest
generally is passable, so that a pedestrian may follow it continuously around
the lake, with the exception of short intervals on the southern side where the
sharpest portion of the rim occurs in Castle Crest. At many points around the
rim of the lake the best route is on the inner side, where the open slope,
generally well marked with deer trails over beds of pumice, affords an
unobstructed view of the majestic sheet of water.
The best way to get a
comprehensive view of the base of Mount Mazama is to travel around the crest of
the rim, but the structure is seen to greatest advantage from a boat on the