The Saturn V is of course the famous moon rocket and all that, but you can't just start at V when you're designing and testing rockets. Instead, you start at I. The Saturn I was NASA's first ever heavy-lift rocket, although really, it was more of a cluster of individual rockets all strapped together and lit off at the same time. Ten flights between 1961 and 1965 (the above picture shows the very first of these) proved the Saturn I's worth for (among other things) testing Apollo modules, so NASA ordered up a beefier version, the Saturn IB, in 1966. Just one year later, NASA decided, heck with it, they were just gonna then skip Saturns II through IV and head straight for the Saturn V.
For the record, there were actually Saturn IIs and Saturn IVs, which were the names for the second and upper stage of the Saturn V. The Saturn III was a scrapped idea for a launch vehicle with a payload in between the Saturn I and V. And, best of all, there were plans for a Saturn VIII (!), which would have used eight F-1 engines. Ultimately, it couldn't be built because the factory where they would have built the Saturn VIII didn't have a tall enough roof.
Every day, DVICE selects fresh images, videos and more from the wonderful world of technology. See them all by clicking this link.