How to select outermost vertices in a shape like this? I have a mesh, in the shape of a geographical state, which I created (rather crudely) following these steps:

Keeping an image in the background,
Adding a plane with 1000x1000 subdivision over it
Selecting vertices which overlap the state image manually
Separating them to form a mesh

The end result looks like this:
Object Mode:

Edit mode (Vertices):

My question is: How can I select the outermost vertices to form a plane mesh with the given shape?
I would like to be able to bevel this shape (and others like it) to represent some sort of data in a WebGL application.
Select Boundary Loop.

First, A Select All
Then in 2 Edge select mode,
Select &gt; Select Loops &gt; Select Boundary Loop
At this stage an option is to PS Separate Selected, to make the boundary edge a new object... or

dissolve (or delete) internal verts to end up with one big ngon state
1 Vert select mode,
CtrlI Select &gt; Invert
Then XD Dissolve Vertices.