SharpMap

SharpMap is an easy-to-use mapping library for use in web and desktop applications. It provides access to many types of GIS data, enables spatial querying of that data, and renders beautiful maps. The engine is written in C# and based on the .Net 2.0 framework.
Category	Geospatial
License	GNU Library or Lesser General Public License (LGPL)
HomePage	http://www.codeplex.com/SharpMap