Facebook/Justin Williams
Of all the places they've been, the Democratic People's Republic of Korea has been the most memorable by far.
They were shocked to see how heavily tourists are supervised there, as well as how little some North Koreans knew about outside cultures.
"It's like traveling to a different world," Justin told Business Insider.
They arranged their trip in 2012 through a
We've put together a collection of images that show what the experience was like for them, from the tight restrictions they faced to the fascinating sights they saw.
For a full set of images, visit Justin's Instagram page.