Inside North Korea: An architectural tour of the world's most locked-down country

As a tour guide for Koryo Tours, Nick Bonner has made week-long trips to North Korea — one of the world's most secretive and least understood countries — once a year for the last 22 years. He does it to teach people about architecture. Bonner recently walked Tech Insider through his tour, beginning at the vaulting Arch of Reunification that welcomes people into Pyongyang, North Korea's capital city, to the resolute Monument to Party Founding — with its stoic hammer, brush, and sickle. Ther...