how to access folder in side a folder?

Hi,

 I created slideshow with ajax slide show extender and I can display images in folder images in root with this code

string path = HttpContext.Current.Server.MapPath("~/images/");

with this code I can access images in folder but my slide show images are in other folder inside Folder images.

string path = HttpContext.Current.Server.MapPath("~/images/SlideshowImages/");

when slide show run display empty images I don't know why??????????

plz help me, THANKS,