Transcript for What Otto Warmbier's tour through North Korea was like: Part 1

Reporter: After a long, heart-rending journey home, 22-year-old Otto Warmbier was laid to rest. Thousands of loved ones honoring a young man whose promise seemed limitless. Mourners wiping away tears, as the hearse wound its way through town to the cemetery. His friends now speaking out for the first time. To now have the opportunity to explain what type of a guy he was, and what he meant to us, each one of us, we're just really grateful for that, because he was just the best guy. Reporter: And on display at the funeral, the quiet testimonies of Otto's belongings, shoes, his wallet, his passport, his jacket. Relics of a journey that began with hope and ended in horror. I net down by his side and I hugged him and I told him I missed him and I was so glad that he made it home. It's just not acceptable and unthinkable. It's a nightmare, really. Reporter: December 29th, 2015. Otto Warmbier was aboard an old soviet jet, crossing into north Korean air space. I've made that trip, too, eight times, in fact, where the onboard announcements welcome you to a nation state which is also a state of mind. Pyongyang is the capital of the juche Korea, the might of Korea is well known to the world. Reporter: Immediately Otto and his travel group hit the ground running, going on a guided tour of Pyongyang, the country's capital. On billboards everywhere, former leader leaders. Agustin Feliciano made a similar trip two months before Otto. We would see Normal north Koreans walking around on the street, people going to work, coming home from work, soldiers going to and from. Reporter: It's a city teeming with military. The world's fourth largest army. Children everywhere, walking in formation, singing praise for their nation. There would be a couple times when we would be, like, is that staged? Reporter: Like the glorious little children at the Pyongyang nursery school. And what are they singing? This is the song of general Kim il-su il-sung. As we watch, we are struck by the uniform smiles, the sin cronized movements. This might not be the average tourists idea of a perfect vacation, but Otto Warmbier wasn't the average tourist. He just loved traveling in general. He just had this sense of curiosity about him. He was never afraid of anything. Reporter: Otto's hometown is the small Cincinnati suburb of Wyoming, Ohio. All American, affluent, known for its top notch schools and tidy tree-lined streets. My colleague Linzie Janis went to visit. We're a close community. A tight knit community? A tight knit community. We look at the warm beibiers as a part of our family. Reporter: The family, Otto's mom Cindy, his dad Fred, who owns a metal finishing company and his two younger siblings, Austin and Greta. Otto, a prom king and soccer star, grew up with this group of high school friends, spending hours together in this basement hangout. And you guys spent a lot of time here with Otto? Every weekend probably. Yeah. He had that special ability to be able to make you feel like you were the only person in the room. He was charismatic? Oh, my gosh. Yes. Funny? Hilarious. He's so intelligent, but he never made you feel stupid. Which was amazing. He never bragged. Oh, my god. He would get the highest on every test and he would never tell anybody. Reporter: Todd siler was Otto's favorite teacher. I thought he was putting me on, the first month of class. I thought, this guy's so enthusiastic, he really can't be this excited about U.S. History. But Otto was a thinking. Reporter: Otto graduated second in his class and was selected to give a speech at graduation. He showed love to his small town roots, but seemed ready to explore. This is our last day together as Wyoming high school's class of 2013. Tomorrow morning, we will all belong to another class, another job or another city. No matter where we go or what we do, though, we will always have this group here. Reporter: After heading off to the university of Virginia, Otto hopscotched the globe, visiting Cuba, Israel and Ecuador. During his junior year, he embarked on a study program in Asia. Otto's father would later show Fox News' tucker Carlson what he had packed for his trip. He's got his uva notebook. Yeah, his passport. This was Otto. Most of this stuff would have been bought at a thrift store. He loved that. He's got a taste for zany shirts. He does. And he looked good in them. Reporter: But then, Otto made a fateful discovery. One which led to a fateful decision. He found a travel group called young pioneer tours based in China and specializing in tours to North Korea. In this promotional video, a tour guide describes the journey. North Korea is a ten-minute walk that way. Here we are in Pyongyang now. There seems to be an atmosphere on fun associated with this trip, let's go to North Korea on a lark. Reporter: Anna Fifield is "The Washington post's" Tokyo bureau chief. She says young pioneers tapped into the adventurous wanderlust of people like Otto. Their slogan is "Tours to destinations your mother doesn't want you to go to." So they are really playing up the whole idea this is off the beaten track. Reporter: Otto's plan was a five-day trip, costing more than $1,000, billed as the new year's party tour. An odd name for a trip into a rogue nation nicknamed the hermit kingdom. It's the ultimate forbidden country left in the world. It's sort of the forbidden fruit. So, I think that's -- that's the cause for excitement for why people want to visit. Do you guys remember the first time he said, "Hey, I want to go to North Korea?" I was excited for him. He's Otto. Another Otto thing to do. Just go wherever, you know? Just to craziest place you could think of. Reporter: After touching down in Pyongyang with the young pioneers, Otto's itinerary scheduled like clockwork. On day two, his group of about two dozen traveled two hours to kaesong and the demilitarized zone. From there, it was onto sariwon city, to interact with locals. Andrew Byrne took the young pioneers tour to North Korea just this spring. He says, before you go, they tell you the rules to be followed. They brief you on how to behave, what not to do. What's expected of you. There's no room for making fun of the kims or taking a photo that's not polite of Kim il-sung or Kim jong-il. Eporter: And for tourists, there are always minders. They move you through attraction after attraction very quickly. It's like checking off boxes. Reporter: But Otto seemed to be soaking it all in. Ready? All right. Ready to throw it at me? Reporter: Even having a snowball fight with local north Korean kids. How would you describe the Otto in that footage? Joyful. Joyful. He's having fun. He was doing what he always did. And what he was best at. That's Otto. Reporter: So far, the North Korea trip is everything Otto had dreamed of. But in Pyongyang, there are places you just don't go. And one of them was right here. The mysterious fifth floor of Otto's hotel. We were kind of given full reign of the hotel, except for one floor. The elevator skipped floor number five. One, two, three, four, six, seven, eight, nine, ten. So, we were told, don't even try to get to the fifth floor. Reporter: And those accused of trespassing learn the hard way. You can check out any time you look, but you can never leave.

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