The contour plot at left shows elevation contours for the NW Oregon and SW Washington Region (click to enlarge). This was generated using the relatively high-resolution satellite elevation data from TOPEX (more info) . Robert MacKay uses this image to ask students to explain the thermal circulation patterns expected through the Columbia River gorge knowing that areas west of the Cascade Mountain range are often dominated by marine air and that areas east of the Cascade Mountain range are typically dominated by continental air. The Columbia River Gorge is quite popular for wind surfing.
Contour Basics is a good online learning activity designed to help students better understand contour plots. Several good additional references related to understanding contour plots are also provided with Contour Basics.