> Cockerell began running tours to North Korea with the company Koryo Tours in 2002 ...

> Ten years later, Cockerell met a North Korean who was working in China, and that man had the contacts necessary to arrange a visit.

Though the article has some later information:

> No doubt a source of pain for the Kim dynasty, the impressive 554m Lotte World Tower in Seoul, South Korea, which was finished in 2017, dwarfs the Ryugyong Hotel.