San Antonio is one of the 10 biggest cities in the country, and it’s got some of the most dangerous roads.

That’s according to traffic data and analytics company StreetLight, which published a new “U.S. Safe Streets Index” ranking 100 metro areas across the country. San Antonio placed 83rd, making it one of the least safe.

To work out the rankings, researchers collected data from various sources, such as the National Highway Transportation Safety Administration and the Bureau of Transportation Statistics. They scored each metro area across five key road safety factors, listed below.

1. Vehicle miles traveled

As the highest weighted factor in the study’s ranking, vehicle miles traveled reflects how much San Antonio drivers actually drive — and “more driving exposure creates more danger for those inside and outside the vehicle,” the study reads. With long stretches of sprawling highways splayed out in every direction, San Antonio drivers often have to travel miles to get to their destination, thus hiking up the city’s VMT risk factor to a score of 89 out of 100 points. 

2. Speed differential risk

According to the study, speed differential risk measures the difference between vehicle speed on the same roadway. This is a key factor because “differences in the speeds of vehicles traveling on the same roads create especially dangerous conditions,” researchers wrote. In San Antonio, vehicle speeds on the city’s complex highways system can vary greatly from lane to lane, raising the city’s speed differential risk factor to a score of 61 out of 100 points.

3. Speed-based pedestrian risk

This weighted factor measures how safe city streets are for those outside of vehicles. Researchers noted that “high volumes of fast-moving vehicles present some of the greatest risk for pedestrians,” who can sustain severe or fatal injuries at speeds above 30 miles per hour. San Antonio ranked among the most dangerous metro areas in the country, scoring 93 out of 100 points for this category.

4. Truck activity

Because commercial trucks are heavy vehicles with limited visibility, their increased prevalence on the roadway automatically makes for more hazardous driving conditions. “They have been a rising issue in communities with the increase in e-commerce deliveries and growth in distribution warehouses,” the study reads. San Antonio’s risk factor was relatively low in this category, scoring 40 out of 100 points. 

5. Residential speeding

According to the study, this key factor measures the percentage of vehicles traveling 5 miles per hour or more above the speed limit on residential roads. San Antonio ranked as one of the safest in the nation within this category, scoring 4 out 100 points. To see how San Antonio’s overall ranking stacks up against other cities in Texas, see the ranked list below.