Boca Grande restaurant. Boca Grande is located on the small street 'Passatge de la Concepció" between the streets of Passeig de Gràcia and Rambla Catalunya that is packed with popular restaurants. At Boca Grande can guests can enjoy cocktails on the first floor and choose from seafood dishes and the oyster bar in the penthouse with terrace and garden. The concept is good food at good prices and efficient service.