I have a very large shapefile with over a million parcels within it.

The problem I am having is that the polygons representing each parcel are very jagged.

What I am looking for is a simple and fast way of essentially "simplifying" these polygons and thus getting cleaner lines out of things.

Naturally, in doing so I need to ensure all parcels are still linked together so there are no spaces between the parcel boundaries.

What's the best way of achieving these objectives?


3 Answers 3


As other's have answered, the generalization tools will help you, but to avoid the gaps and slivers, you will need to have the tool resolve the topological errors Simplify Tool


http://mapshaper.org/ provides an online applet to do that (see here).

Polygon data are uploaded from a shp file, the simplification level can be controlled on-the-fly with a slider bar, and the simplified data can be imported. Of course, the simplification preserves the topological relationships between polygons (no gaps, no overlaps are created). It is very basic but very quick and efficient! There is maybe a limitation on the input file size.

An example:


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Here is another option. If you are just worried about the visualisation of these parcels, then if you import them into a File geodatabase you can then create Cartographic Representations over them. Then the cartographic representations can be easily modified so that the parcels are smoothed out. This will only work in a File Geodatabase and will mean that the actual geometry data can stay as it is.

Another option is, if you received the data from another source you can ask them to provide the data again.


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