QUOTE: Originally posted by murrieta I received a very long, but appreciated e-mail from a collector of Lionel HO that pulled some information out of a hard cover book on the history of Lionel. Rivarossi made the first Lionel trains under contract. HO models were copied from their O scale counterparts in as much detail as possible. Horns were even put in the diesels and many accessories operated just like the O scale versions, much advanced for the day in a HO model. A scale GS-4 Daylight was even built that was far superior to anything Lionel built in 3 rail. Production ended in 1966. Operational accessories were fragile as was to be expected, and few exist in good operating condition. Lionel resurrected the HO line in 1974 using re-branded Athearn locos and cars. This era was successful as the product was reliable and popular, but Lionel chose to focus on their 3 rail line and ceased retail sales in 1977.