Olive was the original sandbox sim, released in SL 1.0. It sparked a lot of debate among residents who lived next to it because of the noise and junk from physics experiments, some of which included the creation and collapse of massive physical towers with some of the pieces landing into nearby residential sims. It was, then, by popular demand, reterraformed as a giant hole similar to the current sandbox Cordova in order to keep physical prims from leaving the simulator and spilling onto residential areas.
Olive was reterraformed yet again in SL 1.1 to cover the hole, marked mature, and divided up. Plots were put into a lottery which residents entered to win the chance to buy these plots. It was an early experiment in restricting primitive allocation by land size.
Cordova then replaced Olive as a full sim sandbox.