One of the oldest treasures in Barcelona is also one of the most hidden. Located in the city’s Gothic quarter, four 2,000-year-old columns from the Roman Empire’s Imperial Period are guarded by the building that houses the Centre Excursionista de Catalunya (Hiking Club of Catalonia).

The temple was built to honor Emperor Augustus and once towered over the ancient Roman city of Barcino. It was constructed of sandstone from nearby Montjuïc Hill and at least partially plastered over. The 120-foot-long building was built in the first century. It was surrounded by numerous 30-foot-tall columns, but now only four remain.

Most of the stones from the temple were reused for other buildings. Three of the columns remained intact, forming part of the inside of a new structure. They were found in the 15th century, but no one could figure out their origin until the 19th century, when it was discovered they were in fact the remains of a Roman temple.

The fourth column was rebuilt from the remains of the other columns and erected in the Plaça del Rei (King’s Square) in 1879, where it stayed until 1956 when it was moved to the spot where it stands now, next to the original three columns, which have never been moved. Though they rest on bits of plinth from the original structure, the ancient building is otherwise gone.