The Secret: You are about to learn the answer to an age-old mystery

You are about to embark on a fantastic adventure:

A quest for twelve treasures: over ten thousand
dollars in precious jewels. They may be hidden in
your city or your local park or even in your own
backyard. You might even figure out one of their
hiding places without leaving your house ....

The First Clue:

At stone wall's door
The air smells sweet

Not far away
High posts are three

Education and Justice
For all to see

Sounds from the sky
Near ace is high
Running north, but first across

In jewel's direction
Is an object
Of Twain's attention

Giant pole
Giant step
To the place
The casque is kept.