Windows下OSGeo4W安装PROJ 4.9.0失败及pip安装Cartopy报错求助

Hey Carl, let’s work through this frustrating Cartopy/PROJ issue step by step—this is a super common headache on Windows, so I’ve got a few tried-and-true fixes that should get you up and running.

It sounds like you might have missed a step or the default OSGeo4W setup isn’t showing the older PROJ version. Try this:

• Re-run the OSGeo4W installer and select the Advanced Install mode (not Express)
• Navigate to the Select Packages screen, then search for proj
  • If 4.9.0 doesn’t show up, click the View dropdown in the top-right and switch from Default to Full—this will display all available versions
  • Check the box for proj-devel (not just the base proj package) in version 4.9.0
• Repeat the same process for geos: search for it, check geos-devel (Cartopy requires this development package, not just the runtime)
• Finish the installation, and note down your OSGeo4W install path (usually C:\OSGeo4W64 for 64-bit systems)

Pip doesn’t automatically detect OSGeo4W’s installed libraries, so you need to point it in the right direction.

Option A: Use the OSGeo4W Shell (easiest!) #

The OSGeo4W Shell automatically sets all the required environment variables for you. Just:

• Open the OSGeo4W Shell from your Start menu
• Run pip install cartopy directly here—this should pick up PROJ and GEOS without extra work

Option B: Manually set environment variables (for regular CMD/PowerShell) #

If you prefer using a regular command prompt, set these variables first:

set PROJ_DIR=C:\OSGeo4W64\share\proj
set GEOS_DIR=C:\OSGeo4W64\bin
set PATH=%PATH%;C:\OSGeo4W64\bin;C:\OSGeo4W64\lib

Then run pip install cartopy

Option C: Install Cartopy with explicit paths #

If environment variables don’t stick, force pip to use your OSGeo4W libraries directly:

pip install cartopy --install-option="--proj-lib=C:\OSGeo4W64\share\proj" --install-option="--geos-dir=C:\OSGeo4W64\bin"

If you still can’t get PROJ 4.9.0 via OSGeo4W, use pre-built Python wheels for PROJ and GEOS:

• Download the correct wheel files for your Python version and system architecture (32/64-bit)
• Install PROJ first, then GEOS:

  pip install path\to\proj-4.9.0-cpXX-none-win_amd64.whl
  pip install path\to\geos-X.X.X-cpXX-none-win_amd64.whl
  

• Then install Cartopy normally with pip install cartopy

Once you’ve installed everything, test it in Python to make sure it works:

import cartopy
import pyproj
print(f"Cartopy version: {cartopy.__version__}")
print(f"PROJ version: {pyproj.__version__}")

If this runs without errors, you’re good to go!

内容的提问来源于stack exchange，提问作者Carl