Topographic Maps of the Alamo Area

[cantador4u]

I would LOVE to see Mark Lemon’s diorama. I would doubly love it if he were to expand it to include all of 1836 Bejar from the Campo Santo on the West side to the powder house location to the East. Going on the assumption that as long as someone else is doing it, it must be easy, maybe he could have it done in the next week.

But being as impatient as I am, I thought that maybe a good USGS topographic map might help me to visualize the lay of the land around the Alamo. It was frustrating because the relief lines get lost amidst all the other information that is crammed onto the map. NUTS! It seemed that the only thing to do was for me to redraw the map so that the relief lines were more obvious. Using the capabilities of Photoshop I did just that. If nothing else the line certainly do show up better.

I used a 1904 topographic map because it would have fewer man-made disturbances than the most recent maps would have. Today’s maps show overpasses and other highway features that don’t appear on older maps.

The first picture shows the relief lines placed over the original 1904 map that they came from. I knocked down the brightness and contrast of the original map so that the lines would stand out.



Using the “layers” feature of Photoshop I have the relief lines separate from the rest of the map and can overlay them onto other maps or aerial photos. Not wanting to waste this resource, and thinking that anything worth doing is worth over-doing, I redrew the streets that existed in 1836. This is the result.



The USGS has something they call the “seamless server” that gives images with terrain height information so I downloaded several of these images for what it’s worth. You can see several highway overpasses East of the Alamo and West of the cemeteries. One thing that caught my eye was an apparent low spot southeast of the Alamo. I don’t know if this is a recent man-made feature or if it represents a long-standing feature. Could it have contributed to the “ponds” that formed east of the Alamo?



I’m hoping that people smarter than I can make some sense of these images and help in our collective understanding of the events that happened in 1836.

- Paul Meske

[TRK]

Paul: Nice work on the topo map overlays! Are those Roman numerals on the hills east of the Alamo of any significance?

I'm not very familiar with the USGS seamless server, but plan on investigating it. On the two images from it that you posted, I'm not able to get my bearings as to the location of the Alamo and the depression you described. Can you post another image with the features indicated?

[cantador4u]

You are very observant. I put those in there because I wasn't sure where the Powder House was and thought that if I identified the various hill tops it would be easier for someone to refer to a location easier than saying "now count 7 lines from the right hand margin and 15 lines up from the bottom..." or some such thing.

I have an obsession with Maps of San Antonio. The closer to 1835-36, the better, and could draw a pretty good map of 1836 San Antonio from memory. I forget that everyone does not necessarily share in my obsessive-compulsive behaviors. Here is the same picture only better marked. The yellow block of color indicates the Alamo Plaza, and I marked Commerce St. Does this help?



The Romero's Attack/artifacts discussion contributed to my need to do this. I was wondering what sort of terrain the "retreaters" were heading to.

- Paul