City of Dallas running (Read 28 times)

I'm planning to do a long run tomorrow (close to around 20 miles or so).  Starting near the much traveled Dealey Plaza, and heading up to White Rock lake doing the full 9 mile loop around there.  White Rock, I know about, but are there any areas in downtown Dallas that should be preferred over others?  Like, are there any bad areas to avoid, or famous places to run past and not avoid?  Please help!  Many thanks again!