This lesson introduces geological maps and explains how to use a key to read the maps. It is 3 of 3 in the series titled "Geology: Reading Geological Maps."

A guide for young learners to understand reading maps and their keys.

A map of the United States showing the results of the House vote on the Tariff Bill of 1828 during the presidency of John Quincy Adams. The map is keyed to show the areas of votes for, against, or non-votes on the bill, and the for or...