I'm trying to use GeoPandas to generate points of intersection between two linear shapefiles. For example, I have a shapefile of pretend pipelines (red) and some crossings (blue).

enter image description here

What I would expect, are points wherever they intersect (green):

enter image description here

However, what I'm getting is just two points like so:

enter image description here

Here's my code:

import geopandas as gpd
pipelines = gpd.read_file(r"C:\Temp\GeometryTesting\Pipeline.shp")
crossings = gpd.read_file("C:\Temp\GeometryTesting\Linear_Crossings.shp")

I would expect this to be the correct code to calculate crossing points:


or even this:


However, both of them return the same result:

0     POINT (147.010039196221 -26.40843953078755)
1    POINT (150.4550260127808 -25.61354916104867)
2                                              ()
3                                              ()
dtype: object

Why am I only getting two points (and two records with no data)? Using geopandas, how can I generate all the crossing points?

1 Answer 1


I have been always doing this kind of things using unary_union. So, as an intersection of two linestring layers you would get a multipoint geometry which I then iterate through.

import matplotlib.pyplot as plt
import geopandas as gpd
import shapely
import fiona

from shapely.geometry import Point, mapping
from fiona import collection
from fiona.crs import from_epsg



Reading data from shapefiles and creating MultiPoint:

roads = gpd.read_file(r"C:\GIS\Temp\Gpd\Roads.shp")
streams = gpd.read_file(r"C:\GIS\Temp\Gpd\Streams.shp")
points = roads.unary_union.intersection(streams.unary_union)

MULTIPOINT Z (316672.9970907159 4141706.877471883 0, 317324.4303508335 4141602.277340039 0, 317738.9541803655 4141848.779893903 0, 318102.8218661814 4141740.856982633 0)

Writing Multipoint to a new shapefile:

schema = { 'geometry': 'Point', 'properties': { } }
with collection(
    r"C:\GIS\Temp\Gpd\IntersectPoints.shp", "w", "ESRI Shapefile", 
    schema, crs=from_epsg(26912)) as output:
    for i in points.geoms:
        output.write({'properties': {}, 
                      'geometry': mapping(Point(i.x, i.y))})

Plotting all data on the same figure:

fig, ax = plt.subplots()

roads.plot(ax=ax, color='black')
streams.plot(ax=ax, color='red')

points_df = gpd.read_file(r"C:\GIS\Temp\Gpd\IntersectPoints.shp")
points_df.plot(ax=ax, markersize=10, color='blue')

enter image description here

  • @Fezter, did using the unary_union help? Aug 21, 2017 at 5:21
  • Indeed it did, thank you. That's why I accepted your answer. I'm now trying to figure out how to maintain attributes from the inputs, I may ask that separately if I don't figure it out.
    – Fezter
    Aug 21, 2017 at 5:51
  • @Fezter, ok great, I just wanted to check! Aug 21, 2017 at 9:08
  • @AlexTereshenkov Note that this code will crash in case of getting a single point At for i in points.geoms: script will crash with AttributeError: 'Point' object has no attribute 'geoms' Nov 4, 2019 at 14:23

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.