Get Physical Filepath From URL?

Is there a way to get the physical filepath from an ASP.NET's URL?

Scenerio: I have an app that is on two severs, but it will now be on lots more, and each server puts it in a different physical file path. Right now I'm doing this:

//for server 1
if (Request.Url.GetLeftPart(UriPartial.Path).Contains(".com"))
{ Application["StoreFilesPath"] = "E:\Data\rootsite\f1\appsite\Upload\"; }
//for server 2
if (Request.Url.GetLeftPart(UriPartial.Path).Contains(".net"))
{ Application["StoreFilesPath"] = "E:\Web\rootsite2\f34\abc\ghi\appsite\Upload\"; }

But what I need to do is something like this:

//for all servers
Application["StoreFilesPath"] = getPhysicalFilePath() +"\Upload\";