From the YMCA website - Swimmobile, a tractor-trailer – later dubbed the “Whalemobile” – with swimming pool on the back of the trailer, was invented by YMCA Director, Gerry Croushore. The swimmoble was driven from playground to playground in Hillside, Linden and Union where it was parked for one or two weeks while instructors gave swimming lessons. The swimmobile was so popular that a gymobile and nursery school trailer were also added.