Many years ago, I did the whole of "Route 66" from Santa Monica to Chicago in my default Beech Baron 58, in FS 2004, following the roads below me. 2,500 miles!
Stopped over at various Airstrips en-route, and posted some screen shots!
It took a few Flight-Sim sessions to complete!
Regularly do the West Coast Highway 1 from Santa Rosa to Frisco to LA, in FSX.
I love following USA roads in; "Ultimate Terrain USA"!
Paul....Road Warrior!....

...!
Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.