The city of Hiroshima on Monday marked the fourth anniversary of landslides that killed 77 people, with residents calling for greater awareness of natural disasters.

This year's anniversary came about a month after devastating flooding and landslides claimed the lives of at least 226 people in western Japan and 113 in Hiroshima Prefecture alone.

Memorial ceremonies were held in various places in the city including Asakita and Asaminami wards, areas hit hard by the mudslides in August 2014.

At an elementary school in Asaminami, about 100 people observed a moment of silence in a ceremony attended by Hiroshima Mayor Kazumi Matsui.

Representing bereaved families, Riko Kihara, 18, who lost her father and older sister, offered flowers at the memorial service. She told reporters, "I just remember that I had a terrifying experience four years ago. Please do not forget the landslides."

At a different site in the same ward, Jun Wakamatsu, 55, and his wife Naomi, 56, placed a bouquet of flowers at a cenotaph, commemorating the death of their 28-year-old daughter Minami Yuasa.

Naomi said she still has dreams of her daughter returning home. "It is so calm here that I feel as if the landslides did not happen. But I am reminded of (the danger of) natural threats," she added.

Hideharu Hatahori, the 61-year-old head of a facility set up by residents in the wake of the landslides in 2014 to raise awareness about disasters, said last month's devastating downpours reminded him of the need to keep talking about past experiences.

"For people to develop a sense of urgency, we have to work hard to tell them about our experiences," said Hatahori, whose home was severely damaged by the mudslides.

On Aug. 20, 2014, a series of landslides washed away or damaged about 400 houses close to mountains. In Asaminami, where Hatahori's facility is located, about 70 people died.

But the area was spared serious damage in last month's flooding and landslides as many residents evacuated early.

Hatahori said many residents in the area may have had a greater sense of urgency than before. "I want people to become more aware so that they can make the right decisions (in times of disaster)."

In last month's flooding and landslides, many people died in other areas already designated as zones facing the potential danger of mudslides. Experts pointed to the difficulties of evacuating and alerting residents in such areas.

To help deal with similar disasters, the Hiroshima prefectural government plans to conduct a survey of residents on when they decided to evacuate and what prompted them to do so during the torrential rains in July.