= Summary =

1. USGS offers new topo maps as a geospatial PDF [http://www.gdal.org/frmt_pdf.html] for download [http://nationalmap.gov/ustopo/index.html].  Direct download of specific file: [http://ims.er.usgs.gov/gda_services/download?item_id=5365522]
2. Some users may prefer to have the Topo map as a geotif rather than PDF

= Details =

1. GDAL must be built with Geospatial PDF support, see the above link for details.  Confirm with: 
{{{
$ gdalinfo --formats
Supported Formats:
...
  HF2 (rwv): HF2/HFZ heightfield raster
  PDF (rov): Geospatial PDF
  OZI (rov): OziExplorer Image File
...
}}}

2. Use gdalinfo to get NEATLINE:
{{{
$gdalinfo OR_Newport_North_20110824_TM_geo.pdf 
Driver: PDF/Geospatial PDF
Files: OR_Newport_North_20110824_TM_geo.pdf
...
Metadata:
  NEATLINE=POLYGON ((420904.431944419047795 4955726.310806447640061,420721.94461186096305 4941719.078548463992774,410694.503490555507597 4941849.71684651542455,410876.990823113534134 4955856.949104498140514,420904.431944419047795 4955726.310806447640061))
Corner Coordinates:
...
}}}

3. Make an OGR datasource of the NEATLINE to use as a cutline in gdalwarp.  This can be two files, a .vrt and .csv
wkt_cutline_file.vrt:
{{{
<OGRVRTDataSource>
             <OGRVRTLayer name="NEATLINE">
                <SrcDataSource >NEATLINE.csv</SrcDataSource>
                <GeometryType>wkbPolygon</GeometryType>
                <FID>Record_Id</FID>
                <GeometryField encoding="WKT" field="wkb_Polygon"/>
                <LayerSRS>EPSG:26910</LayerSRS>
            </OGRVRTLayer>
</OGRVRTDataSource> 
}}}

NEATLINE.csv:
{{{
"Record_Id","wkb_Polygon"
"1","POLYGON ((420904.431944419047795 4955726.310806447640061,420721.94461186096305 4941719.078548463992774,410694.503490555507597 4941849.71684651542455,410876.990823113534134 4955856.949104498140514,420904.431944419047795 4955726.310806447640061))"
}}}

4. Use gdal_translate or gdalwarp to convert to geotif and if using gdalwarp, -cutline to the NEATLINE.
{{{
gdalwarp -cutline wkt_cutline_file.vrt -cl NEATLINE -crop_to_cutline OR_Newport_North_20110824_TM_geo.pdf OR_Newport_North_20110824_TM_geo.tif
}}}


= Notes =
 * There is probably a more elegant way to grab the NEATLINE for use.  (see this thread for some ideas, [http://osgeo-org.1803224.n2.nabble.com/gdal-dev-GeoPDF-translation-td7091018.html GeoPDF thread on nabble])
 * This could be combined with gdalinfo, wget, or curl to determine which file to download.  (This is not the same file listed above but a nearby historical Topo)
{{{
wget "http://usgs-catalog4.srv.mst.edu/cgi-bin/gda?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetFeatureInfo&BBOX=-125.317789,43.823383,-123.427332,45.547829&SRS=EPSG:4326&WIDTH=912&HEIGHT=831&LAYERS=gdagfigeopdfs&STYLES=&FORMAT=image/jpeg&QUERY_LAYERS=gdagfigeopdfs&INFO_FORMAT=text/plain&X=629&Y=335"
}}}

{{{
curl -s "http://usgs-catalog4.srv.mst.edu/cgi-bin/gda?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetFeatureInfo&BBOX=-125.317789,43.823383,-123.427332,45.547829&SRS=EPSG:4326&WIDTH=912&HEIGHT=831&LAYERS=gdagfigeopdfs&STYLES=&FORMAT=image/jpeg&QUERY_LAYERS=gdagfigeopdfs&INFO_FORMAT=text/plain&X=629&Y=335" | grep DOWNLOAD
}}}

Not sure how to GetFeatureInfo with gdalinfo, here is a general GetCapabilities:
{{{
gdalinfo "WMS:http://usgs-catalog4.srv.mst.edu/cgi-bin/gda?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetFeatureInfo&BBOX=-125.317789,43.823383,-123.427332,45.547829&SRS=EPSG:4326&LAYERS=gdagfigeopdfs&STYLES=&QUERY_LAYERS=gdagfigeopdfs&INFO_FORMAT=text/plain&X=629&Y=335"
}}}