The 127 arches under the iconic Long Bien Bridge are being reopened, with work starting last Saturday. The arches were built by the French between 1900 and 1902 to support the railway above, which connects Hanoi with northern provinces. They were sealed more than four decades ago.

"Doing away the arches will not affect the railway's structure," said Nguyen Duc Chung, Chairman of Hanoi's People's Committee.

The city announced the renovation plan in 2017 to turn the area into a tourist hub, saying it was going to use VND100 billion ($4.3 million) from a private source.

Arch 93 on Gam Cau Street, which literally means "under the bridge," in the Old Quarter would be the first one to be cleared, after which 3,600 square meters of space would be freed for cultural and commercial purposes, according to the Old Quarter Management Board.

The sign reads: "Construction work. Sorry for the inconvenience!"

Technical personnel inspected the arch's inner structure by drilling a 10 cm-wide hole through it.

The railroad on top of the arches is reinforced with steel beams to ensure safety for trains as they run through sections where the arches are being cleared.

After an arch is cleared, it is polished and laminated.

The arches are supported by steel beams as construction happens. The first arch is expected to be cleared by June 25.

The 127 arches, each 16 square meters wide, were blocked over 10 years ago due to the vibrations and noise produced when trains ran on the railroad ahead. Phung Hung Street, which the arches lined, has served as a parking space ever since.