the DLG have Level 3 (DLG-3) catego

the DLG have Level 3 (DLG-3) category. DLG-3 data have a full range of attribute codes and full topological structuring, and have passed certain quality-control checks.

The 7.5- and 15-minute DLGs are within the large-scale category; the 2-arc-second DLGs are within the intermediate-scale, and the 1:2 million-scale DLGs are within the small-scale category.

A Digital Line Graph (DLG) is a cartographic map feature represented in digital vector form that is distributed by the U.S. Geological Survey (USGS). DLGs are collected from USGS maps and are distributed in large-, intermediate- and small-scale with up to nine different categories of features, depending on the scale. They come in optional and Spatial Data Transfer Standard (SDTS) format and are topologically structured for use in mapping and geographic information system (GIS) applications.