The area covered by the map is titled in the upper right and lower left corners. A pictorial representation of the area is provided at bottom right. If provided, a symbol key appears at the bottom. Map scale is shown at bottom center. Contour interval is shown at bottom.
Magnetic declination is shown at lower left.
All points on the same contour are at the same elevation above mean sea level. Based on the relief of the landscape, the scale of the map, and the map's purpose. The smaller the scale or the greater the relief, the larger the contour interval. So, if the contour interval is 10 feet, index contours occur at 50-foot intervals. Supplemental contours are used where a given interval is inadequate for a portion of mapped area, as when indicating subtle terrain such as a floodplain.