When trying to install Shapely on my Windows 64bit computer, I cannot get the GEOS library to work.
So far, I have run the OSGeo4W installer from which I installed GDAL (I believe the geos library is included in that package). After that, I checked and I have geos_c.dll on my C:\OSGeo4W\bin directory, but either I have missed some configuration steps or the library does not work.
I need Shapely to work, so I also ran pip install shapely after installing GDAL, and it apparently worked (although it could not find the C library for GEOS).
In my code, I can import Shapely, but when I try to use it, I get an error telling me "geos.dll" is not found.
Best Answer
Uninstall shapely and try to install it from here. Hope it helps. It worked for me.