This chapter discusses various extra-hard cheeses, such as Parmigiano Reggiano Protected Designation of Origin (PDO), and Sbrinz PDO. Raw cow's milk is used to produce Parmigiano Reggiano PDO. The colour of the cheese is between light straw to straw. The aroma and flavour of the paste is fragrant, delicate, tasty but not spicy. Reggianito cheese is a popular Argentinean Grana-type cheese made exclusively from cow's milk. Argentinean legislation defines Reggianito cheese as a low-moisture or hard cheese with a moisture content up to 35.9%, a minimum FDM of 32% and a ripening period of at least six months. The colour of this cheese is white or light yellow and uniform. Sbrinz PDO is an extra-hard, full-fat cheese made from raw cow's milk that is produced in the central part of Switzerland. Sbrinz has a fruity aroma with a slightly roasted character of chicory and a salty and slightly sweet taste.