The camp grew quickly. After the initial 1,500 Australians arrived in 1942, another 770 British and 500 Australian soldiers were added in 1943, bringing the prisoner population to approximately 2,500. The men were forced to construct a military airfield under brutal conditions, with inadequate food, rampant disease, and systematic cruelty. The camp produced its own electricity using a wood-fired steam engine coupled to an alternator, originally part of the agricultural research station's infrastructure. That power system became the unlikely backbone of an act of defiance: from 1942 until its discovery in July 1943, prisoners secretly raised the voltage in the evening hours to power a clandestine radio transmitter, feeding intelligence to Allied forces outside.

Camp commandant Susumi Hoshijima, a military engineer promoted from lieutenant to captain during the war, presided over a regime of deliberate cruelty. When new prisoners arrived in April 1943, he made his authority clear in terms that left no room for misunderstanding. The camp was ringed with barbed wire, and in front of the guards' office stood a wooden cage roughly 1.8 by 1.5 by 1.2 meters -- about the size of a large dog crate. Prisoners caught stealing food from the kitchen were locked inside. As conditions deteriorated, larger cages were built: a second measuring 2.7 by 2.1 by 1.5 meters in June 1943, and a third at 4.5 by 2.7 by 2.7 meters in October 1944. The escalating dimensions tell their own story -- more prisoners were being punished, for the simple act of trying not to starve.

By October 1944, the airfield had become a liability. Allied bombing raids hammered it relentlessly, and by January 1945 the runway was beyond repair. Work stopped on 10 January. The prisoners' labor was no longer needed, but the Japanese had no intention of freeing them. That same month, approximately 455 prisoners were forced to march westward through the jungle toward Ranau, roughly 260 kilometers away. The men were already weakened by years of malnutrition and disease. Stragglers were shot. In May 1945, the Japanese decided to close the camp entirely. Captain Takakuwa Takuo took command on 17 May. Twelve days later, he ordered the remaining 536 prisoners to march to Ranau, then set the camp on fire, destroying almost all records of what had happened there.

The dominant structure of the camp was not a building but a tree. A towering specimen of Koompassia excelsa -- known locally as the Mengaris tree -- rose above the compound, visible to every prisoner and guard alike. It became an involuntary witness to three years of suffering. The tree did not survive the postwar years, but today the site has been partially transformed into Sandakan Memorial Park, dedicated to all who suffered and died here and on the marches to Ranau. A concrete water reservoir and baseplate from the Japanese kitchen facility still remain, physical remnants of a place where thousands of men were worked, starved, and ultimately marched to their deaths. The park stands as a permanent reminder that some ground carries a weight that ordinary use cannot erase.