Shoe manufacturing has been one of the city's main economic industries, and regularly, the city has been referred to as ""a Capital do Calçado"" ("the Capital of Footwear"); many of Portugal's shoe manufacturers and ancillary businesses, including the "Centro Tecnológico do Calçado" ("Footwear Technology Centre") and "Centro de Formação Profissional da Indústria do Calçado" ("Footwear Industry Centre for Professional Learning") are based in São João da Madeira. Similarly, regional industries have been responsible for the production of 20% the world's felt hats and continues to be the major national producer. The quality of São João da Madeira's head apparel has, at one time, been recognized internationally, and incorporated in fashion house (such as Hermès). In addition, the movie industry was responsible for supporting this industry, with headwear produced for films such as "Public Enemies","Indiana Jones and the Kingdom of the Crystal Skull" (Indiana Jones' hat, for example) and the Mad Hatter's famous hat in "Alice in Wonderland". Other secondary industries in the economy include automobile components, industrial textiles, mattresses, glues and tubing manufacturing, which are concentrated in four industrial zones: Travessas, Orreiro, Devesa-Velha e Oliva.