How to build a safer city

Denser cities have an inherent advantage in walkability, and older cities often have more rail infrastructure. But Helsinki also employed plenty of modern interventions that other cities can learn from, Streetsblog notes.

• Wide sidewalks and narrow traffic lanes prioritize people over cars, and the city has almost 750 miles of protected bike lanes.
• Helsinki also has gradually lowered its speed limits. Most local roads now have limits of about 20 mph, and major arterials are as low as 37.

Go deeper: In a study published in January, an international group of researchers studied the road and transit layouts of nearly 1,700 cities, breaking them down into nine types to analyze their safety.

• Unsurprisingly, density, short blocks and the availability of mass transit all contributed to fewer injuries.

The bottom line: "The best approach is to get people out of cars in the first place, and to design cities in ways that people are using motor vehicles less," one of the study's authors told Fast Company.