Birkenstock Footprints Loreto Leather Boots Footprints licensed by Birkenstock. Made in Portugal. 100% Birkenstock natural cork footbed Leather Upper . Leather Footbedliner. Polyurethane Sole. Lace up boot with full zip on the side. Touch-fasten tongue. Padded back collar. Only selected styles feature full side zipper. See color tabs.