New Vintage USGS 24k DRG topo

Boyd

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Continuing on my current nostalgia trip, I have just published a new map of the vintage USGS DRG Topo's we used twenty years ago. These were the first digital versions of the 24k topo maps available from the USGS. They were also used by terraserver and topozone and I have updated my link translators to use them, for a period-correct experience. There's quite a difference between them and the high-quality USGS historic topographic maps used in the boydsmaps Legacy 24k Topo - you can compare them here

https://boydsmaps.com/sync/#16/39.663498/-74.523647/drg24k/0/0/legacy24k/16/0/0

But these were created in the 1990's, when internet connections were very slow and it was important to reduce the size of images. The maps were scanned at 250 dots per inch, which is similar to the 300 dpi scans of the maps in the historic topo collection, but they severly constrained the palette to only 12 colors, creating a lot of problems. This approach could work well with all-digital maps, but the colors were just not consistent enough on the old paper topo's and it resulted in artifacts and a lack of clarity.

But in spite of their shortcomings, I think they are historically significant enough to justify inclusion at boydsmaps. Like other recent maps, they cover the US Midatlantic region. Although these maps were available everywhere twenty years ago, in 2025 it was a challenge to find download sources. The core of the map actually consists of terraserver data that I downloaded with the USAPhotoMaps program back around 2004! See the Map Info for more details.
 
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Boyd

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Jul 31, 2004
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Ben's Branch, Stephen Creek
Just a footnote here, I'm expanding this map to cover the entire US Northeast region. Since it's getting harder to find these DRG's, now's the time to grab them before they completely vanish. Just found an obscure archive of DRG's at the USDA NRCS (Natural Resources Conservation Service) for every state. So, I will also replace the non-DRG portions of the existing map in this update.

The quality of these NRCS DRG's isn't as good as some of the others, but they're good enough and are the only source I've found for CT, RI, MA and VT. I found some very high quality DRG's for Maine and New Hampshire and already have good sources for the other states.

Downloading is slow, but hopefully the expanded map will be available by the end of next week.
 
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Boyd

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Jul 31, 2004
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Ben's Branch, Stephen Creek
Just noticed a big difference between the DRG topo and my legacy topo. Somehow, I ended up with a much older version of this quad. The Garden State Parkway must have only been a proposal when that map was made - note that the location is way off from where it was actually built (the DRG map on top is correct).

https://boydsmaps.com/sync/#15/39.653559/-74.344288/drg24k/0/0/legacy24k/15/0/0

Screen Shot 2025-06-08 at 3.41.32 PM.png


In other news, predictably, the expanded DRG version is taking much longer than I hoped - it's a LOT of data. But it's coming. My computer was running so hot and getting so slow, I was concerned. Shut everything down, opened it up and it was completely clogged with five years of cat hair and dust to the point that hardly any air was moving through it! Did a thorough cleaning and what a difference! (duh) :D
 
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