The border of China, Russia and North Korea. （Photo provided to China Daily）

"It was the first time I have crossed the border on bike, which made it particularly special. I had been a little worried about the sand, but it really wasn't that bad at all, and in fact a little more comfortable than riding on asphalt. There was a nice holiday feel about it, rather than the idea that it was a competition."

Sun says that for him the highlight of the trip was the hospitality and salt-of-the-earth nature of the Koreans they met, as well as the fresh air.

"To ensure everything was safe and that we had everything we needed, we had two Korean guides make the trip with us. Everything, including the food was good. The seafood and potato pie was great, and I can still taste it now."

Sun's girlfriend accompanied him on the trip.

"Road conditions were much better than we expected," the girlfriend, who did not want to be named, says. "As long as you have a bit of riding experience it's not going to be too hard for you. I've been asked about women doing the trip, and the only thing I would say is not to forget to take suntan lotion with you."

Piao says cyclists have warmly welcomed the tour and it has been oversubscribed for this month.

"For me one of the most gratifying things is that we are getting all sorts of people - men, women, the young, the old and the retired - who are interested in coming along."

Getting on the tour is relatively easy, he says - as long as you are Chinese. Chinese nationals can sign up through a bicycle club anywhere in China, "and with a valid passport you can get permission to join in two or three days".

Restricting the tour to members of bicycle clubs reflects the fact that it is new, and as a tourist "product" there is still room for improvement, Piao says, including with the route, which he feels at the moment is "too simple" and lacks sightseeing attractions.

"I hope we can open up more routes in the future. The key thing at the moment is that we can guarantee the safety of those who do the tour."

Sun also sees scope for more routes.

"I was born in the Northeast and am strongly attracted to the sea. To be honest, I was a bit disappointed that even though on the tour we were able to eat seafood, we did not get the chance to ride along the coast. I hope they can include a beach route soon."

Tourists entering the DPRK are prohibited from taking mobile phones and cameras with them, and Sun says he hopes such rules can be relaxed in the near future.