Kala'din was a ancient city on the planet Ryloth whose demise became the basis of a moral tale. The story, known as «The Fall of Kala'din», was often retold by Twi'lek mothers to their children as a reminder of the importance of keeping secrets.
The Legend of the city Kala'din
Thousands of years ago there was a sister city to Kala'uun known as Kala'din. This city produced so much ryll that it held its own against slavers and spice merchants, and was the most powerful city on Ryloth.
A Twi'lek called Kroh'dalla lived in Kala'din, and was second supervisor to the Ryll Master. He oversaw operation of the ryll mines and processing vaults, and it was his duty, like all other Twi'leks who knew of the mines, to keep their location secret from all others. But Kroh'dalla was greedy, and wanted more money and prestige for himself and his clan than he was paid by the miserly Ryll Master.
One day a spice merchant and slaver named Brophys landed at Kala'din to purchase a load of ryll for sale. Now Brophys was known to many Twi'leks and others throughout the galaxy as a rich merchant who would cut a deal with anyone to make more credits. Kroh'dalla approached Brophys when he landed, and offered to reveal the location of the ryll mines and processing caverns if Brophys would give Kroh'dalla 100,000 credits and make his clan the city's ruling clan.
But after the deal had been made, and Brophys' mercenaries had invaded the mines, Kroh'dalla and his clan were forgotten. The ryll mine workers were killed, Kala'din's remaining citizens were enslaved, and Brophys relentlessly dug ryll from the extensive caverns beneath the city. He and his men mined so much ryll in such a short time that the very foundations of the city collapsed into the mines, destroying Kala'din and killing the greedy mercenaries who deceived Kroh'dalla into revealing the mines' location.
For once a secret is revealed, it spreads, like the ryll mines of Kala'din, until all the truth above is destroyed.