I love heritage railroads and railway museums. The only thing cooler than trucks, when I was a kid, were trains. My uncle worked for CN for many years, retired now. My cousin apparently took his place.
Canadian Pacific has a rare example of early high power diesel in storage at a museum in Quebec. A Fairbanks-Morse H-24-66 "Trainmaster" built by Canadian Locomotive Company in the 1950's. 2400hp 203L 12 cylinder opposed-piston supercharged two-stroke diesel engine. CP operated several of these, with the last ones finally leaving service in the 1980's. CP 8905 is the only intact example of a Trainmaster left, stored in inoperable condition, sadly. The traction motors were repurposed and the engine was reportedly in serious need of an overhaul it was never going to get. Apparently the opposed-piston engines had a very unique sound.
The only cooler locomotive of that era, in my opinion, was the UP Gas Turbine aka Big Blow. They make awesome noise, tons of smoke and put down 8000hp. The only sufficient replacement for the Big Boy.