The Oyster Bar and Restaurant exterior showing the Guastavino tiles. Guastavino tile is the "Tile Arch System" patented in the United States in 1885 by Valencian (Spanish) architect and builder Rafael Guastavino. Guastavino vaulting is a technique for constructing robust, self-supporting arches and architectural vaults using interlocking terracotta tiles and layers of mortar to form a thin skin, with the tiles following the curve of the roof. The iconic landmark of the oyster Bar is located in the lower level of Grand Central Terminal Station in Midtown Manhattan, New York City, New York.