Tourists seek out Mexico's darker side

What’s next?Parasailing over North Korean airspace? Parachuting over Somalia? Swimming with crocs in the Nile?

Travelers sign up for a mock border crossing or tour of a dangerous slum

While most travelers flock to Mexico to sip margaritas on white-sand beaches, a hardy few choose lesser-known tourist sites where they are chased down by immigration agents or risk their lives in dangerous slums.