The Fountain of Youth

The Fountain of Youth was the target of Age of Empires III's main villains, the Circle of Ossus.

Game Info
The fountain spent its time in the "Lake of the Moon", somewhere in Florida, until the events of Act I: Blood. Then it became at the centre of a massive battle involving the circle, the Knights of St. John, Elisabet Ramsey's pirates, Sahin's Ottoman companies and whatever native tribes were around at the time. It was destroyed using a large mounted gun the Circle had mounted on the far side of the lake, and if you were playing good enough, a bunch of mortars posted outside their base. With the Fountain destroyed, the circle mostly went off back to Europe to replan their moves, with there being nothing left for them here. Without the water source, the lake drained and became a swamp by the events of Act III: Steel, where the circle tried to dig up lost Spanish treasure ships and possibly, if they went deep enough, into the spring the fountain came from.

Trashing it
As said earlier, the easiest method of destroying it is gradually pounding it into the ground using the Fixed Gun on your side of the lake, but you have to protect it from the circle's Navy. If you aren't playing on hard, it should be fairly easy also once built up to push toward the circle's base with several mortars, or simply to land them on the small island near the base and have them help to pound the fountain into dust. You could also just keep sending in Fire Ships to ram the fountain, if the Circle's navy doesn't destroy them first.