Lisbon Battles With Itself Over Its Fabled Tile Sidewalks

“Lisboners have a love-hate relationship with their distinctive sidewalks – painstakingly crafted from five-inch cubes of limestone since the 19th century – that flank most of the city’s streets.” But that limestone gets very slippery when wet, and “officials have stirred passions with a plan to make one of the world’s oldest cities a safer place to walk.”