- Go to the National Viewer page: http://viewer.nationalmap.gov/viewer/
- Zoom to an area encompassing the sections you wish to download (Tip: double left-click your mouse pointed at the area you're interested in until you reach the desired extent)
- Click on the "Download Data" button in the upper-right of the viewer
- Click the link in the popup window "Click Here to download current map extent
- From the new popup, check the box for "Elevation" and from the drop down menu to the right select "BIL_16INT" and click the "Next" button
- In the next window, select from the available packages and click "Next"
- The selection will appear in the left menu - click the "Checkout" button
- Enter your email address to receive the links to the data download