The United States Geological Survey (USGS) makes a wide array of data available to the public through their "Seamless" server. Among this data is topographic information. The following tutorial will walk you through downloading this topographic data from the website.

1. In your web browser, disable all popup blockers. (This website relies on popups and will not function properly if blockers are enabled.) Then, navigate to the seamless website: http://seamless.usgs.gov.

Finding your data:

2. Click "View and Download United States Data." This will take you to an interactive map where you can select the area for which you would like to download information.

3. The main interface of the seamless server is relatively simple to use. Use the "Zoom" tools to zoom into your area of interest. Use the "Pan" tool to move around the map. These tools are located on the left of the screen. To display different layers of information to help you navigate, use the "Display" menu on the right of the screen.

4. Once you have zoomed in to the area for which you are looking for information, click "Download" on the right side of the screen to access the list of data layers available for download for that region. Select (by checking the boxes) the data layers you would like to download. Note that several different types of information are available. For the purposes of this tutorial, we will select the 1-second National Elevation Dataset (NED).

5. Once you have selected the information you would like to download, use the "download" tool (on the left side of the screen) to draw a box around your area of interest. If the box is red, then the area you are selecting is too large to download at once. (You will have to do more than one download.) If the box is green, then your area is small enough for a single download.

6. A new window will open with thumbnail previews of the data you will download and a description of each of the files you selected. In this case, the area we selected is represented in two files. Click the "download" button to download your data.

7. At this point, another window will open and your download request will be added to the "queue." Requests are processed in the order in which they are received. Your data will be packaged in a .zip file when ready. Save your file, then unzip it. Your raster elevation dataset is now ready for you to use in ArcGIS.