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In Network Analyst, I want to create a center line from a road polygon layer of an area for shortest path creation. How do I do this in ArcGIS 10?
check out ET GeoWizards for ArcGIS. it has some features for finding center lines.
i hope it helps you...
If you have the ArcInfo licence you can use Collapse dual lines to centreline tool. This is in the Cartography Toolbox.
Alternatively, if you have Data Interoperability Suite, then you will have FME. There is also a tool in FME to get centerlines from polygons.
If you don't have ArcInfo licence or FME, go with Aragon's suggestion.