# Creating perimeter around multiple polygons using ArcGIS for Desktop?

This may have a simple answer that I'm just missing.

I have multiple polygons in one shapefile I would like to make a larger Polygon around all of them.

Is there a tool that is able to do this?

Or even a Polyline would work if that is not possible, I can always do the Feature to Polygon tool after.

The images below better explain what I am looking to do (second is just a quick polygon I drew in a few seconds).

It is in order to show different sales areas for my company.

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You might want to create the convex hull around the group of polygons. This is a fairly common tool available in GIS. – WhiteboxDev Sep 2 '14 at 19:49

## 1 Answer

Using Minimum Bounding Geometry with the "Convex Hull" option checked, should yield your results.

EDIT

While this answer it accepted and has 4 upvotes it is a wrong answer. The correct answer is to use "Concave Hull". See the details from the comments below.

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Concave hull would be better for this use case ubicomp.algoritmi.uminho.pt/local/concavehull.html. I have no idea if ArcGIS has a tool for it. – user30184 Sep 2 '14 at 19:52
there is concave hull in ET geowizard, but not in the free version ian-ko.com/ET_GeoWizards/UserGuide/concaveHull.htm . Convex hull will not work in this case. – radouxju Sep 2 '14 at 19:58
Alpha shapes look also interesting doc.cgal.org/latest/Alpha_shapes_2/index.html – user30184 Sep 2 '14 at 20:05
@GravitaZ Another similar option, if you have an Advanced license, is Aggregate Polygons. – Chris W Sep 2 '14 at 20:53
@GravitaZ It seems odd to accept Convex Hull as an answer and then to say that Concave Hull solved it. Was it the answer from Maksim that solved your problem or the comment by radouxju? If the latter I think you should ask radouxju to post an answer to that effect so that you can accept that instead. – PolyGeo Sep 2 '14 at 21:30