How to set Swagger as default start page?

Add this routing in RouteConfig.cs as commented out here:

public static void RegisterRoutes(RouteCollection routes)
{
    routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

    //ASP.NET Web API Route Config
    routes.MapHttpRoute(
        name: "DefaultApi",
        routeTemplate: "api/{controller}/{id}",
        defaults: new { id = RouteParameter.Optional }
        );

    // Set Swagger as default start page
    /*
    routes.MapHttpRoute(
        name: "swagger_root",
        routeTemplate: "",
        defaults: null,
        constraints: null,
        handler: new RedirectHandler((message => message.RequestUri.ToString()), "swagger"));
    */

    routes.MapRoute(
        name: "Default",
        url: "{controller}/{action}/{id}",
        defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
    );
}

For a RESTFUL API in ASP Net Core >2.2, set the default URL in Project/Properties/ Debug

I know the main question was for ASP.Net MVC, but for ASP.Net Core a good solution from this answer on a similar question (using SwaggerUI): https://stackoverflow.com/a/50127631/1179562

app.UseSwaggerUI(c =>
{
    c.RoutePrefix = "";
    ...
};