Harrison is a blue American diesel-electric hybrid locomotive.
Harrison is a real strong diesel engine and the fastest engine from Chuggington, he thinks he's the cat's whiskers (the vents on his face even make him look a bit like a cat). It doesn't help that young Wilson looks up to him like a hero. Though he is vain and prideful he leans towards the vanity levels of Sir Reginald as opposed to Gordon or Farnsworth, he is a hardworker and when he gets his comuppance, he has the courage to own up.
Harrison is based on the Union Pacific Railroad M-10003. It was delivered in May, June, and July 1936 from Pullman-Standard, with prime movers from the Winton Engine division of General Motors Corporation and General Electric generators, control equipment and traction motors. One was for the City of San Francisco, two were for the City of Denver, and one was a spare set intended for both routes. The locos ran until they were replaced by E8 locomotives in 1953, at which point they were scrapped.
- Harrison is good friends with Chatsworth.
- Harrison is Chuggington's fastest diesel ever.
- He is Wilson's role model and sometimes a mentor to Wilson.
- Harrison was once a trainee with Chatsworth as stated in Watch Out Wilson.
- He is easily a smarty-pants to the other chuggers.
- In German and Latin America he is called "Harry", In Czech he is called Rychlovous (episodes 1-26, 53 onwards), which means Fastbeard. However, after it was revealed that there would be another chugger called "Harry", his naming in the German version was changed so that Harry is only a nickname now.
- In Polish, he is called "Hektor".
- In Hebrew his name is אוהד.