They've made it this far, but now the most important leg before they officially race for $1 million has finally arrived for the teams on The Amazing Race, and as they head to China for the penultimate leg, the competition will finally heat up.

Burnie and Ashley, Matt and Dana, Cole and Sheri and Tyler and Korey will all head to Shenzen for their last international stop before they come back to the U.S. and try to be the first ones to cross the ultimate finish line. And with the conclusion so close, all four teams are ready to finally get in touch with their more competitive sides.

"We can taste it," Tyler says in a preview clip for the Friday, May 6 episode.

However, China for their final leg will prove to give the teams some very confusing challenges, as they not only have to navigate mazes of streets, but deal with the challenge of recognizing landmarks from all over the world at the Windows of the World exhibit, something that proves to be more difficult than they all may have realized.

"I've got to find the Vatican," Burnie says in the clip as he stands near a replica of the Colosseum.

Overall though, it come down to navigation when the teams try to get to Phil and assure their place in the final leg, and when that comes into play, it could be anyone's game. But, it could also be the thing that proves to do in perennial underdogs Sheri and Cole, who have suffered from navigational failures before.

"I think my mom is lost," Cole says in the clip.

"Golly, this is going to be tough," Sheri says.

Of course, any of the other teams could also falter and make a fatal mistake, meaning a strong team could suddenly find themselves out of the running when the race comes back to the United States.

The Amazing Race airs Fridays at 8 p.m. on CBS.

Tags: The Amazing Race CBS Reality TV