[AccessD] OT - Relative URL

I am using Visual Studio 2005 Express to create a web site.  It is a 
subset of a larger website and sits in a subfolder to the main web site.

I have the default.aspx in a directory called /root1/Subroot1.  This 
is where my web site begins.  I would like to link to an image in 
/root1/Subroot2.

What is the syntax for a relative URL to move from Subroot1 down to 
root1 and then up to Subroot2?