Trips up the escalators for fresh air are rare, and brief. Their eyes, so used to their new dim surroundings, hurt in the sunlight. Her sons Nazar, 6, and Makar, 3, are scared of being outside.

“The kids hear the bombs go off and they want to come down again,” Igorivna, 31, explained. “Every day I want to go out for a walk, but I can’t. I just want to go home.”…

For some residents who remain, the city’s metro system, built to withstand nuclear war, feels like the safest place to be. Tents and mattresses dot the platforms, while the subway cars have been parked with their doors open to give a little more shelter. Children chase each other on the escalators, the favored playground in this underground village.

“It’s like a small town and I’m the sheriff,” said Olek Kucha, as Igorivna’s younger son, Makar, clings to his hand. There are about 50 kids living in this one station, among around 200 or 300 people. They’ve drawn pictures supporting the Ukrainian armed forces that have been stuck on one of the station’s marble columns.