The Iceberg Lounge was created by the Gate brothers in the late 19th century for Theodore Coblepot. 
The Iceberg Lounge is a trendy Gotham City nightclub, and is the base of operations for the Penguin.
Seemingly tiring of the criminal lifestyle, Penguin went "legit" and began running a posh nightclub, "The Iceberg Lounge". He has three new beauties running his club for him in his absence; Jay, Raven, and Lark. The Iceberg Lounge is the hottest place in town according to Gotham's jaded in-crowd. The preening Penguin enjoys the good life, but he hasn't entirely abandoned his criminal ways. Using the club as a front, the Penguin secretly continues to control Gotham City's underworld by trading in illegal information and stolen goods.
The two-story, 12,800-square-foot restaurant and lounge includes a large pool for pet seals and penguins in the center dining area, an iceberg-like sculpture in the pool, a ship themed dance floor, and polar decor. A tuxedoed jazz band on the sculpture is often seen playing tunes.
The Penguin has his own private dining area, upstairs near the bar where he can oversee everything. Some of the nightclub's more secret areas include the Penguin's office and armory, and some of the Iceberg Lounge's hidden back rooms, which serve various criminal purposes.
Batman often infiltrates the Iceberg Lounge to keep an eye on The Penguin's after-hours activities, usually under the guise of Matches Malone.
When Penguin's crime ring of kidnapping pregnant girls was discovered, the Iceberg Lounge was the target of a vicious attack that destroyed the penthouse of the building.
After Black Mask became crime lord of Gotham, Penguin abandoned the city and left the Iceberg Lounge utterly empty. Black Mask used the building as a hideout and base of operation for some of his henchmen including Mad Hatter and Alexandra Kosov.
When Batman went missing, Robin broke into the Lounge coming through a window and looking for some answers. A few days later, Batgirl went to the Lounge and also questioned Penguin about Batman's location. Her abrupt interruption caught the attention of Johnny Stitches and Intergang, who were frequent visitors of the Iceberg Lounge, much to Penguin's dismay. The Lounge was the chosen place for supervillains like Killer Croc, Mr. Freeze and Man-Bat to eliminate a great faction of Intergang and regain control of the city. Penguin allowed them to destroy the place to get rid of Intergang and then used Intergang's money to repair the damage done.
The DC Universe heavily changed its continuity into the DCnU following the events of Flashpoint in 2011. This was part of an effort to make storylines more accessible to newer readers, beginning with the New 52. This new timeline combines elements from the DCU, Vertigo Universe and Wildstorm Universe while drastically changing the origins and histories of characters.
Penguin reopened the Iceberg Lounge under a new name; the Iceberg Casino. It is now a floating casino and hotel just outside of Gotham, designed like a sparkling iceberg. A secret backroom was the meeting place for some of Gotham's newest villains, such as Hypnotic, Mister Combustible, and Mister Toxic. Not long after its grand opening, the villain Snakeskin attempted to assassinate the Penguin, but was shot before he could succeed.
Rumors began spreading that Lady Shiva was coming to Gotham to kill organized crime. Heeding the warning, Penguin closed down the casino, packing his valuables as he planned to seek shelter somewhere else.