(Phoenix, AZ) -- One of the country's most dangerous stretches of highway runs right through Phoenix. I-17 comes in fourth on a list of the deadliest highways in the nation. And the portion that runs through Phoenix is the most dangerous stretch, according to a study by the GPS tracking company, Teletrac Navman. From 2011 to 2015 there were 123 fatalities on I-17 between Flagstaff and Phoenix. 49 of those deaths were inside Phoenix city limits. An Arizona Republic analysis finds that from 2013 to 2015 the most deadly sections of I-17 were from Bell Road to Greenway Road and from Happy Valley Road to the Loop 303. The deadliest stretch of highway in the country is I-4 in Florida between Tampa and Daytona Beach.