Achao's 18th-century Jesuit church, Iglesia Santa María de Loreto, on the south side of the Plaza de Armas, is Chiloé's oldest (1740) and also a Unesco World Heritage site. Crowned by a 25m tower, it has alerce shingles and is held together by wooden pegs rather than nails. The church has been slowly restored, with new wood juxtaposing the old, but its restoration has remained faithful to the original design.
