The Mexican military escorted a 10News crew to the tunnel. It is a sophisticated system that demonstrates what drug cartels will do, in order to get drugs into the U.S.
The tour begins at an Otay warehouse district of Tijuana inside an unsuspecting building just like hundreds of others in this bustling business park.
The elevator shaft is almost 40 feet deep.
10News Anchor Steve Atkinson enters the tunnel.
The tunnel has a motorized rail system.
"We can only spend 15 minutes down there, because it’s very hot -- and there's very little ventilation," said 10News Anchor Steve Atkinson.
The tunnel is unfinished and it is unclear where it was intended to end.