DLG Map

http://www.dnr.sc.gov/GIS/descdlg.html

DLG stands for Digital Line Graph. These are vector images, meaning they are not based on pixels but on mathematically defined lines, which means that the image can be condensed or blown up to whatever size without quality loss. These maps have 9 possible categories of features they can show through layers, including PLSS, BD, TR, HY, HP, NV, SM, MS, and SC.