. >> the skaters raced through the tunn at dsf up to 40 kilometersn hour. no cars, no pedestrians, and because a lack of proper safety installations has repeatedly delayed the tunnels opening, their fun is guaranteed to continue, but they have to be fast to avoid security guards. >> i just love the feeling. it's your adrenaline --ure adrenaline. >> this is the best skate ramp. not just in problem, but in the world, i think. >> but the instruction of the tunnel was anything but fun for the residents. entire blocks of houses were in danger of collapsing, so the cotrucon cpanyook measures like this -- steel beams run through this living room. he often hits his head on them. >> it looks like a factory here. i sleep in this room, and i'm always whacking my head on that thing. my wife as wel she puts pillows on the beam, but it does not help. >> the tunnel has people throughout the city worried. the earth beneath prague shook every now and then, and suddenly, a whole. it had not been there the day before -- suddenly, a hole appeared that had not been there the da