This paper analyzes the relationship between road network structure and speeding using GPS data collected from 152 individuals over a 7 day period. To investigate the relationship, we develop an algorithm and process to match the GPS data and GIS data accurately. Comparing actual travel speed from GPS data with posted speed limits, we measure where and when speeding occurs, and by whom. We posit that road network structure shapes the decision to speed. Speeding is large in both high speed limit zones (e.g. 60 mph (97 km/h)) and low speed limit zones (less than 25 mph (40 km/h)); in contrast, speeding is much lower in the 30 - 35 mph (48-56 km/h) zones. The results suggest driving patterns depend on the road type. We also find that if there are many intersections on the road, the average link speed (and speeding) drops. Long links are conducive to speeding.