Scud Running and Drugs.
Just say NO!
Its been a VERY long time since low level VFR nav could be considered a reasonable alternative. Not since before they started shoving all manner of man made structures up all over the country - 1000' high microwave link towers/ high tension power lines etc.
About the only thing that is safe to follow low level these days is a beach/coastline if you stay over water.
Roads (they usually put the tall, thin microwave towers next to roads - the guy wires have a large footprint) valleys and rivers, imho, are very dangerous.