For many office workers in Istanbul, the workday no longer starts at 9 a.m. It starts whenever they manage to defeat the city's traffic.

As congestion continues to shape daily life in Istanbul, some commuters heading to the busy business districts of Levent and Maslak have adopted a strategy that would have seemed unusual a few years ago, arriving at work hours early and sleeping in their cars until their shift begins.

In what could be described as Istanbul's newest unofficial hospitality sector, parked vehicles outside office towers are increasingly doubling as temporary bedrooms, dressing rooms and entertainment centers.

Many workers leave home as early as 5 a.m., armed with pillows, blankets and a determination to avoid the traffic jams that can transform a relatively short commute into a multi-hour ordeal.

Some spend the extra time sleeping behind the wheel. Others watch videos on their phones, take morning walks or prepare for the day before stepping into the office.