The Alchemical Door, also known as the Alchemy Gate or Magic Portal ( or Porta Magica), is a monument built between 1678 and 1680 by Massimiliano Palombara, marquis of Pietraforte, in his residence, the , which was located on the Esquiline Hill, near Piazza Vittorio, in Rome. This is the only one of five former gates of the villa that remains; there was a lost door on the opposite side dating them to 1680 and four other lost inscriptions on the walls of the mansion inside the villa.