“I expect the coast will take off at least 5000 chests of the new Bengal drug, providing we are not interrupted by the Mandareens. Merchants from other ports make a point to come here for their opium."

John Rees in Chimmo Bay to William Jardine in Canton, 1.18.1836*

Shenhu Bay (深滬灣), known to the British opium merchants as Chimmo (also Chimo, Chimmoo), is an inlet approximately four miles across and strategically situated between the large ports of Xiamen and Quanzhou. The bay is big enough to provide shelter in rough seas, but small enough to defend effectively. It was also far enough away from seats of government power to avoid constant surveillance, but located along a major coastal shipping line between two large ports. With Xiamen twenty-five miles to the south and Quanzhou fifteen to the north, the bay was perfectly suited for Jardine-Matheson's purposes. Shenhu Bay remained an important opium smuggling depot all the way until 1860, when implementation of the 1858 the Treaty of Tianjin de facto legalized the importation of opium.

Though it was located out of the way from the two neighboring ports, the anchorage at Shenhu bay could not have been "secret" in any meaningful way. The area was densely populated, and no local residents would have missed the arrival of foreign opium ships. As the above photograph and this video both illustrate, anyone with access to the water would have seen the British opium ships, which were anchored in the bay every day between 1833 until 1860. Any boats from shore that visited the ships would also have not been able to do so in secret, unless at night. But the Jardine-Matheson archives record daytime sales in abundance. People for the most part felt safe and secure enough to paddle out to the ships in the middle of the day and purchase large quantities of opium. Perhaps they paid an attached fee that made them feel more confident in their security.

*Source:JM:B2 7 [R. 495, No. 74] Rees to Jardine, 1.18.1836