I managed a ride on the Dallas Santa Fe Trail this morning. It takes you from White Rock Lake to just outside of Downtown Dallas. A nice and easy ride of maybe 5 miles from the White Rock Spillway to to Downtown. You end up in in an odd part of town for a cyclist and I suppose if I knew downtown or Deep Ellum better I would have know what to do it looks like the trail definitely ends with no expectation of further development, even though the trail itself is very well constructed.
As an aside it is cool to see the remains of the original Dallas Santa Fe Rail Line at the end of the bike trail pavement.