Ember Island
"Something is wrong on Ember Island."
That was what she had been told by the captain of the Fire Navy ship that had stopped her. Katara had been sailing south in a little canoe designed to be quickly propelled across the seas with waterbending. She had been going home for the first time in a while, and had decided to cut through now-friendly Fire Nation territory, close to their old hideout on the resort paradise of Ember Island, when she had found the Fire Navy blockade. She turned aside to the capital, wanting to help.
Fire Lord Zuko explained it