It's harvest season for California's $11 billion cash crop marijuana.

But to understand its problems, you have to get high.

See all those shiny straight things?

Those are all marijuana growers.

There's so much marijuana being grown in the state

that there is a massive surplus.

We found a lot of it is being smuggled east

to states where it's yet to be legalized.

A 300-pound load stopped in Missouri,

800 pounds in Idaho,

3,400 pounds in Texas.

Did this all happen too fast?

Oh, my goodness. Of course it did.

Tonight, a history lesson turned detective story about what may be the first blockbuster news story ever published,

solving the mystery of the stolen Christopher Columbus letters,

written more than 500 years ago by the explorer himself,

announcing his discovery of the new world.

He actually made the globe a globe,

and that's pretty much the most consequential news ever published, isn't it?

It's not easy to get to.

But for centuries, pilgrims have made their way to a place where faith, mystery, and miracles coexist.

The story of these 11 Ethiopian churches, each carved from a single block of stone,

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