AMERICA can seem like a scary place. Tourists familiar with American television programmes like The Wire may worry that they will find themselves in a hail of gunfire. Such fears are misplaced: Americans are three times as likely to die in car accidents than in shootings.

While traffic deaths have fallen tremendously over the past 50 years, American roads are still far deadlier than their European counterparts. Much of this can be explained by population density, as the chart above demonstrates. As in Europe, many cities in America's north-eastern states were laid out with horse carriages rather than cars in mind. Streets are narrower there; pavements are crowded with pedestrians and cyclists, leading to slower traffic and safer roads overall.

Big open states to the west on the other hand, like Wyoming and Montana, have far deadlier roads. People commonly drive long distances at high speeds on mostly empty roads, and it can be easy for drivers to lose focus. Social attitudes are often different too: fewer people use seatbelts, and drunk-driving is more common. The wide open road is a dangerous place.