You can do something like this:
private static readonly string[] StaticPages =
{
"FaQ", "Help"
};
/// <summary>
/// Registers the routes.
/// </summary>
/// <param name="routes">The routes.</param>
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute("StaticPages",
"{id}", // url
new { controller = "StaticPages", action = "Show" }, // defaults
new { id = String.Join("|", StaticPages) }); // constraints
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional }); // Parameter defaults
}