The concept is simple: Keep the spirit of Wynwood's emerging street art scene, only curate it more tightly. Commission 15 muralists from around the world to cover the outdoor space. Add grass, tables, and a basketball hoop. Open it to the public free of charge. That's what collaborators Tony Goldman and Deitch Projects did on a still-gritty stretch of NW Second Avenue, next door to Joey's Italian restaurant. At the bright, enclosed space, each painter gets his or her own towering wall, which serves as a sort of urban canvas. It's a great place to sit, have a cup of coffee, and talk. One wall displays the face of a Burmese woman; another boasts a cartoon duck; a third shows spacey, graffiti-like patterns. The project began during Art Basel 2009. Now, 15 more walls are on the way, and it still feels like a secret.