Until a few months ago, life was relatively peaceful in Kyiv when compared with the situation near the war's front lines elsewhere in Ukraine . Now, as Russia expands its attacks on the capital, Kyiv has increasingly become a front-line city.

With too few shelters for the 4 million residents of Kyiv , subway stations double as makeshift dormitories. Starting at about 10 every night, people create sleeping areas with mattresses and small tents. Children snuggle up to adults; pets seek comfort from their owners or find a spot among strangers between the cold walls.

"We're alive," Halyna told DW, holding her 5-year-old son, Roman, close. "We've been lucky once again." Most evenings — even when no air-raid siren has sounded — she takes the boy to the nearest subway station.…