The night market on April 1 Street in Cat Hai District, a well-known tourist attraction opposite Cat Ba Bay, was completely devastated.
All 45 souvenir kiosks were blown away by the typhoon.
Nguyen Thi Hue, a kiosk owner, estimated the damage to her business at hundreds of millions of dong (VND100 million equals US$4,061).
"My father is 85 years old, and he said he had never seen Cat Ba so severely damaged by a storm," Hue said.
Hotels and restaurants along April 1 Street, considered the most beautiful location on Cat Ba Island, were among the hardest hit.
According to the People's Committee of Cat Hai Island District, 4,717 houses were damaged across the district, though the full extent of the damage has yet to be determined.
The typhoon's power was so intense that it even warped an air-conditioner of a hotel on Nui Ngoc Street.
When Typhoon Yagi made landfall in the Quang Ninh - Hai Phong area on Saturday afternoon, it brought maximum wind speeds of 149 kph.
Huyen Chi, a consultant for Cat Ba Island tours, considered herself "lucky" as her company's kiosk managed to keep its rolling door intact, though the corrugated iron roof and other assets were damaged.
The steel roof of the Hung Long Hotel was completely collapsed.
Most of the steel-framed and corrugated iron-roofed structures on Cat Ba Island were either blown away or collapsed.
One restaurant on April 1 Street lost its roof, had its glass doors shattered, and saw all its interior furnishings destroyed by the typhoon.
Le Manh Hiep, owner of Dolphin Hotel 230, said the damage to tourist facilities was "huge", adding that his family alone suffered around VND500 million ($20,300) in losses.
"Any place that wants to welcome tourists will need at least a month to recover," Hiep said.
Staff at LePont Cat Ba Bungalow on Cat Co 3 Street have been cleaning up the debris for three days, but the work is far from complete.
The resort complex, situated on a mountain overlooking the sea, bore the full brunt of the typhoon and was almost completely destroyed, resulting in damages estimated at VND10 billion ($406,400).
Fallen trees, broken signs, and collapsed structures have created a massive amount of debris on Nui Ngoc Street.
The transformer station near Tung Dinh Lake, in the center of Cat Ba, was knocked down by the typhoon and has not yet been restored.
The entire island has been without power since Saturday.
The road through the gate of Cat Ba National Park remains hazardous, posing risks to both pedestrians and vehicles.
Thousands of trees, 12 hectares of perennial fruit trees, and 19 hectares of crops on the island were damaged.
Tourist attractions such as Thien Long Cave, Thien Cung Cave, and Trung Trang Cave have all ceased operations until the damage can be repaired.
