Alcatraz - Telegraph Hill Maps

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High-resolution relief maps of Alcatraz and Telegraph Hill are available, with streets visible from one-third arc-second resolution. However, the small vertical differences might not be apparent on printed maps. The Alcatraz map features both high and low tide versions, considering an 8 feet tidal range. Data sourced from USGS National Map, which offers elevation data in various formats and resolutions as "tiles." A Fortran source code is included, generating openSCAD code to create relief maps. Upon printing Alcatraz.stl and Telegraph_Hill.stl on a Replicator, the former took 30 minutes while the latter took around 2 hours. The input file for the Fortran program was floatn38w123_13.flt, containing 10812 by 10812 floating point numbers without additional info. Note that maps are uncorrected and potential data errors might exist in treatment. Alcatraz island's sea levels were near zero and 2.4 meters, while Telegraph Hill's was close to USGS zero.