US Topo - 15 of 29

US Topo FAQs - 29 Found

Why was the PDF file format selected for US Topo maps?

US Topo is intended to serve map users who are not GIS specialists. The priority design objectives were to create a traditional topographic map as a digital document that can be displayed on a normal office computer without specialized software, and printed at map scale without specialized software or expertise. We believe PDF is the only format in common use that satisfies these requirements. PDF is also the only commonly used format that can carry raster data, vector data, and formated text annotation.

The geospatial extensions add limited GIS functionality "for free" – no cost to end users, and no conflict with base PDF. Users who are not interested in geospatial functions can still use the product as a plain PDF. Further information about GeoPDF is available at this Wikipedia website, and in the US Topo and Historical Topographic Map Users Guide.

Software to display PDF documents is common for all operating systems. US Topo maps are designed and tested to assure correct display in Adobe Reader (v9.x and later) with the TerraGo toolbar geospatial extensions. Both programs are free and can be downloaded at: Adobe Reader and TerraGo toobar.

Though PDF viewing software is common, not all viewers implement PDF layers, which are a key design feature of US Topo maps. We do not know of any PDF software for mobile devices that implements layers.

Tags: Maps, Topographic, Recreation, Quadrangle, GeoPDF, Scale