The famous Lion Gate at the citadel of Mycenae is an example of a tomb portal with forward-looking architectural decoration.

— Deborah Fritz from Marvin Trachtenberg and Isabelle Hyman. Architecture: from Prehistory to Post-Modernism. p80-81.

"...a massive trabeated portal was built into the wall, with cyclopean jambs and lintel, surmounted by a triangular relief of two heraldic lions standing at a (Minoan) column, the sacred symbol of the earth that they supposedly protected. For all its simplicity, the Lion Gate is of immense historical portent. The powerful sense of structure was an inheritance—ultimately Neolithic—that the Greeks would foster with exceptional refinement. Here, it was combined with the feeling for monumental stone carving in the Lion relief, an element inherited from Egypt but now infused with a new sensitivity to the organic logic and beauty of its subject."

— Marvin Trachtenberg and Isabelle Hyman. Architecture: from Prehistory to Post-Modernism. p80-81.