SMILE Factory

The SMILE Factory is a hidden facility that lies near the secret underground trade port of Dressrosa. As the name of the location implies, the factory produces the artificial Devil Fruits known as SMILEs.

Appearance and Layout
From the outside the factory is a circular building with a dome shaped roof. The inside of the factory contains machines and large tanks for processing and storing SAD, and takes on the appearance of a large garden/greenhouse. There are trees and bushes growing the SMILE fruits, the trees are surrounded by a river, the river has walking bridges for people to cross. Whether the river is water, SAD or a mixture of both is yet to be confirmed. At the top of the dome roof is a collection of luminescent sunflowers, known as Elegant Sunflower (エレガントサンフラワー) pointing downward towards the trees. The sunflowers appear to come from the Flower Field, as they share the same crisscross pattern.

The facility is situated underneath the Corrida Colosseum, and next to the Officer Tower, the centralization of Dressrosa's underground trade port.

Factory Method
The SMILE fruits grow from the trees within the factory. The luminescent sunflowers at the top of the factory provide light to the trees. SAD, the essential substance used for the process that only Caesar Clown could produce, is poured into the river, the river has holes on both sides that channel the river under the trees to feed them. Whether or not the river is water, SAD or a mixture of both is to be confirmed.

Once the fruits have grown, the dwarves harvest them and put them on a trolley cart. Even though the Tontatta dwarves excel at plant growing, they still have trouble growing the fruits as they are highly unnatural. Only one-tenth of the fruits from the crop are usable.

Past
Eight years before the Battle of Marineford, when Doflamingo returned to Dressrosa and usurped the throne from Riku Dold III, he captured 500 dwarves and forced them into slave labor to produce SMILEs in the factory. Their usefulness in producing these fruits is from their extensive knowledge of plants, their impressive strength compared to their miniature sizes, and their naivete nature making them easy to deceive.

Dressrosa Arc
When the Straw Hats first arrived on Dressrosa, they split into three groups, the group consisting of Luffy, Zoro, Sanji, Franky and Kinemon had the goal of finding and destroying the SMILE factory as well as rescuing the samurai.