Motorists in North Jersey's most crowded cities and towns not only confront crawling traffic and darting pedestrians on a daily basis. They face one other challenge: getting around in places where they're far more likely to get into a collision than in most other parts of the state.

An analysis of crash data maintained by the state shows that four times more collisions occurred per mile of roadway from 2015 through 2017 in the most densely populated municipalities in New Jersey compared to the statewide average. The difference jumped to more than ten-fold over the rates in some rural communities.

Those gaps pile up mostly in traffic-clogged areas of Hudson, Bergen, Passaic and Essex counties, including Jersey City, Paterson, Palisades Park, Hackensack and Edgewater, where an average of 24 collisions per year were reported on every single mile of roadway. That worked out to an average of one per year for every city block.

Leading the way was the borough of Guttenberg in Hudson County, a four-block wide shoe box of asphalt, brick and concrete that also happens to be the most densely populated municipality in the nation. There, 594 crashes — everything from fender benders to a fatality — were reported on 4.6 miles of roadway, or 43.1 per mile per year.

On average throughout New Jersey, each mile of road featured 7.2 crashes per year. And in some of the least populous towns, the average dropped below one.

Six of the top seven communities with the highest crash rates were in Hudson County, helping to make motorists there the next most collision-prone in the state.

What makes the data most meaningful is that it doesn't merely show way more crashes in urban wards versus horse havens.

Looking just at raw numbers, New Jersey's 50 most densely populated municipalities combined had 73,000 crashes per year from 2015 through 2017. Roughly 23,000 people a year were hurt or died.

The 300 most sparsely populated towns combined had about 61,000 crashes and 21,000 casualties.

But the contrast becomes clearer when incidents are broken down by mile of roadway.

In the 50 densest locales, there were an average of between 21 and 43 crashes, and five to 13 deaths and injuries, per mile of asphalt. (The vast majority were injuries.)

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That was more than twice the rate of even the next group of towns — part urban, part suburban places like Ridgefield Park, Clifton, Maplewood or Morristown.

And it's more than 10 times the rates in some of the rural, peacefully named corners of southern and western New Jersey — places like Stillwater in Sussex County, Harmony in Warren County, Lower Alloways Creek in Salem County or Tabernacle in Burlington County.

The place with the most peaceful roads from 2015 through 2017?

The Township of Walpack in Sussex County, home to 16 people in 24 square miles and two crashes.