The three in the bucket had nowhere to go. They were ill and being rehabilitated, and the largest had an infected shell.

A worker picked up the smallest, handing it to me. I mistakenly touch its tender underbelly and it snaps.

“It’s not a toy,” one of our group complained. “She is suffering.”

But it wasn’t wise to have too much pity – if it recovered, it was destined to be eaten.

The Taedonggang Terrapin Farm outside the North Korean capital had shipped tens of thousands of Chinese softshell turtles to restaurants across the border and aimed to boost production to 100,000 animals annually. The farm’s deputy director, translated by ever-present government agents, boasted they had sped up the turtles’ growth rate so they could reach 500 grams within months and a kilogram within a year.

Once they reached the requisite size, they were popped into turtle-shaped ceramic pots and boxed for transport.

An attempt was made in 2008 to survey China’s 1499 turtle farms, which concluded at least 300 million turtles are sold each year – and likely many others on the black market. The North Korean farm would only add a fraction to the supply, but banned exports are essential to the Hermit Kingdom’s economy and keeping the Kim regime in power.

Frogs and fish are also bred en masse in the tanks – a shining example of efficiency, we were told. The frogs stared at us but the fish went unseen below.

Warm and humid, aside from three foreign interlopers and the guides, the greenhouse was a hive of inactivity; we had come on a rare public holiday in the depths of winter and there was no one to be seen.

The aquaculture was a small part of the food production enterprise the guides were keen to show off. An orchard said to be 1100 hectares (95 per cent apples, the rest berries and citrus), a piggery and the fish/turtle farm share the same water sources in a collectivised arrangement, with resources and housing centralised.

As the daily temperatures were only occasionally threatenening to get up to zero, nothing was in bloom. At a lookout showing off the vast crops, there was little movement to be seen in the distance. Outside the turtle farm, one man was consigned to guard duty. Keeping him warm was a jacket with a thick collar and cuffs of dog fur.

The farm opened late in the life of dictator Kim Jong-il. On inspecting the facility, he had said: “Truly this is more than a turtle farm, you have earned the right to call this a turtle factory.” For the staff, this seemed a source of pride.

Son and successor Kim Jong-un apparently had a different reaction when he visited in 2015. The state-run Korean Central News Agency reported the young dictator was disappointed in the officials’ “incompetence, outmoded way of thinking and irresponsible work style” for, among other things, failing to breed lobsters that had been bequeathed to them. A large number of turtles had died from a lack of food and clean water, according to Seoul’s Daily NK website. The director, too, had been summarily executed.