Yosemite, Part 1

Hiking and Climbing in Yosemite

Part 1: Reading a Contour Map

If you're not familiar with Yosemite National Park in northern California, click here for a map that will orient you to its location and major features. Close the map window or click on this window to return here. (Source for map: National Park Service Yosemite maps site.)

Our primary object of study in this module will be a contour map of a small portion of Yosemite Park, centering on Tenaya Canyon -- where real hiking (as opposed to our virtual activities) is dangerous and strongly discouraged. The link will open a new window for the map, and you may switch to that window whenever you need to. You will find it useful to print the map from that window -- and in Part 2 the paper copy will be essential. Click here for the contour map.

Identify a cliff on the contour map. How can you use the contours to tell you how steep the cliff is? (The scale of the map is approximately 1 cm = 1000 feet.)

Identify two mountain tops. How can you use the contours for this? Record the approximate altitude of each peak.

The following figure shows the famous Half Dome. How is this landscape related (if at all) to your answers to questions 1 and 2? (For additional pictures of Half Dome, visit the Virtual Yosemite site.)

"Half Dome at Sunset", National Park Service Yosemite site

Locate a saddle point, that is, a point at which the terrain is level, but from which you can go either up or down, depending on the direction you go. Give the altitude at the point on the terrain. What features on the map help you locate this point?

What is the altitude at the shore of Mirror Lake? If you hiked northeast from Mirror Lake along Tenaya Creek, what would be the average slope of your path? Suppose there were a sign at the start of the trail that told hikers “__% grade.” What number would be in the blank?

If you wanted to hike from Mirror Lake to the saddle point you found in step 4, what route would you take? Describe the trail as explicitly as you can, and describe any features of the terrain that might make this hike difficult. (For views of Mirror Lake, visit the Virtual Yosemite site.)