Preferred node for read on Availability Group in a multisite configuration We are going to set up a multi (at least 2) site configuration, and we want to achieve both HA as well as a good resource usage.  

The sites will be interconnected through a high speed, dedicated fiber network, so latency will generally be very low. 

However we still prefer that each site uses the nearest secondary server for read intent data. 

Is this possible?
It is possible, but it isn't an out of the box configuration.  What you would need to do is setup a separate DNS named which points to all the secondary servers that you want to route requests to.  Then setup the read only routing to point to that secondary DNS name.  Then assuming that AD is setup correctly when people are redirected to that DNS name they'll always go to the local one.