Quinta da Regaleira is the strangest and most rewarding of Sintra's many estates. The 20th-century palace and its elaborate gardens were commissioned by the wealthy António Monteiro and designed by Italian scenographer Luigi Manini in an exuberant neo-Manueline style heavy with freemasonry and alchemical symbolism. The gardens are a labyrinth of grottos, tunnels, and secret passages, and the highlight is the Initiation Well — a nine-storey inverted tower you descend into the earth on a spiral staircase. Give it at least half a day.
Quinta da Regaleira
Mystical estate with grottos, tunnels, and an initiation well