There are five candidate locations for Ptolemy's Stone Tower along the Silk Road.
<p>Map draw with input from source:
Thomas, James Oliver, <i>History of Ancient Geography</i> (1948), Fig 56, page 308.
</p><p>Basemap from USGS EROS Archive - Digital Elevation - Global Multi-resolution Terrain Elevation Data 2010 (<a rel="nofollow" class="external text" href="https://www.usgs.gov/land-resources/eros/coastal-changes-and-impacts/gmted2010">GMTED2010</a>), 
Earth Resources Observation and Science (EROS) Center
</p>
Rivers and Locator map made with Natural Earth. Free vector and raster map data @ <a rel="nofollow" class="external text" href="https://naturalearthdata.com">naturalearthdata.com</a>.
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