The motoring industry is in the midst of an SUV revolution, and automakers seem determined to make each new vehicle even bigger and taller than the previous model no matter what. 

But 50 years ago, vehicles weren't getting taller, they were getting longer. The term "boat" didn't come around by accident, and cars from the '60s and '70s were both wider and longer than any other era. No manufacturer was more guilty than Cadillac, as GM strived to give their luxury customers the most bang for their buck. 

Here are 20 photos of old Cadillacs from back when luxury cars resembled boats.