Delta Island is located in the New World. It was the location of the Pirates Festival. Gol D. Roger and his crew first came across this island not long after he was crowned King of the Pirates. There, he learned that his crew had created an Everlasting Pose of Laugh Story secretly, which he immediately threw away.
One Piece Episode 895 "Special Edition! The Strongest Bounty Hunter Cidre"
One Piece Film: Stampede
Buena Festa and Douglas Bullet had planned to organize the Pirates Festival on this island to end the Great Pirate Era and usher in a new one. They hoped to draw as many renowned pirates and Marines as they could. They also needed the Marines to launch a Buster Call on the island. They successfully planned this, using the Laugh Tale Eternal Pose as bait. Bullet used his power to completely destroy the island.
However, with the help of Crocodile and CP0's Rob Lucci, the Worst Generation's Monkey D. Luffy and Trafalgar D. Water Law, Shichibukai Boa Hancock and Buggy, Revolutionary Army second-in-command Sabo, and Vice-Admiral Smoker of the Marines, were able to defeat Bullet.
Even though the Marines managed to capture a large number of pirates, the Revolutionary Army aided a small number of them in escaping. Due to Bullet's defeat, the loss of the riches (by Luffy's hand), and a large number of Marines remaining on the island, the Buster Call was also canceled.
With a circular lake in the middle, the island is divided into three equal pieces by three large rivers. With towering cliffs surrounding it, the landscape appears to slope upwards to the lake in the middle. A few substantial spikes that overlook the middle lake are there as well, and it's covered in vegetation.
Most of the river and coastal banks had been turned into a harbor, and several businesses and other structures had been erected next to it. Around the beaches and throughout the interior, a few towns are scattered about. For observing the events, audience stands were built around the cliffs of the main lake.
An underwater cave beneath the main lake can create a knock-up stream and a small island known as "Treasure Island," enclosed in a huge bubble. Treasure Island was demolished by a bullet, and its remains fell back into the central lake.
The first island in the anime to take the name Treasure Island was the Island of Rare Animals.
A. Delta Island is located in the New World.
A. The Pirates Festival was held on Delta Island.
A. Gol D. Roger and his crew first came across Delta Island.