Chiwan ancient fort lies east of Chiwan Village in Nanshan District. Built during the reign of Emperor Kangxi in the Qing Dynasty, it was a proof to the then coastal defense facilities.
On the way to Chiwan on bus 226, which you can now catch at the Shekou Sea World bus stop on the new Shekou Metro Line, there is a stop called Zuo Pao Tai, or Left Fort (literally Left Cannon Platform). If you get off there and walk up the road winding around the nearby hill, you'll find the partially restored remains of a gun emplacement from the days of the Opium Wars in the 19th century.
This was when British and American merchants were illegally importing opium into China for social and economic reasons. The emperor demanded the trade be halted immediately.
Imperial commissioner Lin Zexu stamped out the trade and destroyed the opium stocks held by foreign merchants upriver in Humen. The British Government then sent troops and ultimately effected the first of what came to be known as the Unequal Treaties. (The former British occupation of Hong Kong was one effect of these treaties.)
The Left Fort, then, was a key point of defense when the British troops were sailing up the Pearl River to Guangzhou. Today you can see one of the 12 guns, and a marvelous statue commemorating Lin Zexu's role in the affair.
Also on site are the remains of the barracks, ancient trees, and a platform with a panoramic view.