AS-500F, the facilities checkout dummy vehicle, rolled out from the assembly building on 25 May 1966, five years to the day after President Kennedy's challenge. Despite the attendance of many Apollo program dignitaries, the Saturn vehicle stole the show. Like the Trojan horse of old, the first glimpse of the emerging Saturn vehicle was awesome. The crawler experienced little difficulty carrying its 5,700-metric-ton load to pad A. During portions of the trip, the transporter operated at full speed - 1.6 kilometers per hour. The Saturn vehicle reached the top of the pad at dusk and was secured two hours later. Understandably, the success was a joyful occasion for KSC and the entire Apollo team. The operation proved the soundness of the mobile concept.
SOURCE: NASA SP-4204 Moonport: A History of Apollo Launch Facilities and Operations (Washington, D.C.: , 1978). By Charles D. Benson and William Barnaby Faherty.