On Sunday night, a London woman walking her dog was followed by a man who yelled obscenities at her and threatened to rape her.

She called the police, and the man was charged with swearing in a public place.

But on Monday, the woman, who only wants to be identified as Maureen because she fears for her safety, also marked the incident on a new interactive map of London that asks women to pinpoint where they've felt unsafe, whether in the last week or in the last few years.

"I'm mad. I'm angry about this. I shouldn't have to feel this way. I should be able to walk my dog when I want," said Maureen, who was among the first women to use the interactive map.

Maureen said the man came out of a dark area in a field near her home as she walked her dog.

"He started yelling at me, but I didn't know if he was yelling at me or if he was just angry at the world, so I just kept walking," she said. "That seemed to infuriate him. He was yelling at me, telling me he would rape me, he would assault me. I became concerned, I did a shoulder check, saw that he was following me, so I called 911."

Police quickly came and took Maureen's statement.

"I was shaking, I was scared," she said. "It was very uncomfortable to repeat the things he was saying to me."

The man was charged with swearing in a public place.

"I felt threatened. It feels like there should be something else, some other charge. I live in what I consider a safe neighbourhood. I feel bad for women who have to deal with this every single day."

Pinpointing unsafe areas

The mapping project, Safe City London, is part of the UN Safe Cities initiative, for which city council has given $31,000.

Women can put pins on the map until December. They can also put pins on places where they've felt particularly safe, said AnnaLise Trudell, who works for Anova, which is partnering with the city on the project.

The mapping software asks women what happened, what time of day and asks them to share as much as they feel comfortable.

Examples of safe places on the map will be used to inform how to make other places more safe, Trudell said.

"This is not random data gathering, this will inform urban planning around particular parks, changes to our transit system, and other changes that the city has committed to making," she said.