In January 10, the batteries of the Nizam began bombarding the outer blockhouses of Chaul, reducing them to rubble after a few days. One such piece earned from the Portuguese the nickname "Orlando Furioso". At the same time, about 2,000 horsemen of the Nizam proceeded to devastate the lands owned by Portuguese around Bassein and Daman, but were repelled trying to assault a small Portuguese fort at Caranjá near Bombay, defended by 40 Portuguese soldiers. In February, a small fleet of 5 half-galleys and 25 smaller craft with 2,000 men from Calicut, commanded by Catiproca Marcá, arrived in Chaul to meet up with the forces of the Nizam, under cover from the night. The Portuguese had five galleys and eleven foists in the harbour, but the Malabarese avoided clashing with the Portuguese galleys. Fighting around Chaul broke down to trench warfare, as the army of Ahmadnagar dug trenches towards Portuguese lines to cover from their gunfire, amidst frequent Portuguese raids. The Portuguese dug counter-mines to neutralize them. In late February the Nizam ordered a general assault on the city, but was repelled with heavy losses, just as the Portuguese received important reinforcements by sea from Goa and Bassein. Fighting continued over the possession of the outer strongholds along the months of March, April and May, as the army of the Nizam suffered heavy casualties. Following a sortie of the Portuguese in April 11, the Nizam ordered the city to be subjected to a general bombardment, which demolished several strongholds and sunk the Viceroy's galley anchored in the harbour. In June 29, the Nizam ordered another mass assault but after six hours fighting, they were repelled, suffering over 3,000 dead. Following this setback, the Nizam requested peace on July 24, 1571, and withdrew his army.
Question: How many months did the fighting around Chaul last?
Answer: 4