This ASP.NET XmlSiteMapProvider greatly simplifies sitemap file maintenence! It provides "inheritance" for pages that do not have an entry in the sitemap file! It is also "default document aware" (no need to specify default.aspx in your sitemap file!), correctly provides sitemaps for sites that use content negotiation (no ".aspx" extensions on your URLs!), and provides a "wildcard" sitemap matching possibility for use when your URLs contain query string variables.