VanMarmot wrote:kepPNW wrote:aiwetir wrote:I'd love to see that map again without spending that $8 USGS wants for the old maps.
I believe you can
download most, no?
Yes, you can download USGS maps at different scales dating back years at that site. Similar USFS maps (good for forest roads) can be found at
USFS maps. The USFS maps tend to mirror the USGS maps, so you might find the same errors on both. Still, the error rate is staggeringly small relative to the number of maps involved.
In this instance, the contour lines not aligning properly seems to be the result of a map join and not an error within a given map. CalTopo shows this joining issue quite often.
Part of this is inherent in mapping in general. Because the 'standard' USGS quads are 7.5" maps, they're covering 7.5 minutes of latitude and longitude, and are
slightly trapezoidal, and will cause some alignment issues when you try and stitch them all together.. The whole flat faces on a spherical surface bit.. It's also good to be aware that different maps have different contour intervals, so your topo lines may double, or half, at the borders.
Nesmith is a prime example of this:
It's easy to tell in the steep face, but can look more like an alignment problem in the flatter areas unless you pay close attention to the contour interval and realize it shifts from 40' to 80'
So when I find them I tend to take note and have started to collect them 
