Equipped with power tools, city crews swept through Center City and West Philadelphia this week to pick up abandoned bicycles ahead of Pope Francis' visit next month.

Workers from the Mayor's Office and the Streets Department collected 73 bike frames in the semiannual cleanup, said Denise Goren, director of policy and planning at the Mayor's Office of Transportation and Utilities.

The sweep, with the aim of clearing sidewalks and parking areas, began Wednesday morning in West Philadelphia and continued Thursday in Center City.

The effort comes just over a month ahead of the weekend of Sept. 26 and 27, when the city hosts 1.5 million visitors to see Francis, who that Sunday will celebrate the closing Mass for the World Meeting of Families outside the Philadelphia Museum of Art.

Before the roundup began, workers tagged about 140 bikes with requests that their owners pick them up, Goren said. The Mayor's Office is donating abandoned bikes that were not claimed to a local charity, Neighborhood Bike Works.