Task: Question Answering
Input (English): Passage: During the continuous skirmishing of the 1260s, both sides employed Muslim soldiers, mostly Turcopoles, against their Christian foes. In 1266, the Genoese had made an alliance with Baibars, who was to outfit some troops for an expedition against Acre, but the Genoese' promised fleet never got underway. In 1267, Genoa managed to capture the Tower of Flies and blockade the harbour of Acre for twelve days before being evicted by a Venetian flotilla. The ongoing warfare between Genoa and Venice had a major negative impact on the Kingdom's ability to withstand external threats to its existence. Save for the religious buildings, most of the fortified and defended edifices in Acre had been destroyed at one point or other  and according to Rothelin, the continuator of William of Tyre's History, 20,000 men in total had lost their lives, a frightful number considering the Crusader states were chronically short on soldiery. The War of Saint Sabas was settled in 1270 with a pact to cease the hostilities between the Venetians and the Genoese. In 1288, Genoa finally received their quarter in Acre back. 
Question: How many years after the War of Saint Sabas was settled did Genoa finally get Acre back? 
Answer type: Number 
Output (English): 18.