Fortaleza Horizonte was a trading post and a fortaleza created by investors from Simbopolis during the colonial expansion of the Federation of Tugal in the Median Era. The fort provided Simbopolis with buyers who were potentially interested in the trade of lindories, including many traders from the bustling port city of Altadena, and it provided Altadena a means of achieving great wealth.

The Tugali War of Unification cut off Fortaleza Horizonte from its Simbopolian suppliers. A breakdown in communication between Simbopolis and Altadena ultimately led to the Horizontian War, which occurred at the same time as the war in the Tugali homeland. The first battle of the war was fought at the fort, and the fort was captured and temporarily occupied by the military of Altadenica. The Altadenican Falando later voted to abandon the fort, which had lost its value after Altadenica had made itself enemies with the Federation of Tugal. The abandoned fortification was temporarily used as a pirate base by independent raiders of Aerumaen descent before the Great Simbopolis Flash Flood (which encompassed much of the Simbo River valley) destroyed it.

Today, only ramparts remain. The fortaleza's ruins are presently uninhabited.