A database of speed obtained on a road located in the Pasto (Nariño department) in southwestern Colombia. The analysed road sector has a total length of 27.5 km and is developed in a predominantly mountainous topography. The data collected corresponds to the geometric characteristics of the road, as well as the design, traffic and operating speeds of each element throughout the sector. The data series corresponds to 312 elements of the geometric design, which are located continuously along sector. The design and road speed for each element, was determined from the geometric characteristics of the road; meanwhile, the operating speed was determined using spot speed data, which was obtained from field measurements with the Bushnell Radar Gun. For the determination of the Operating Speed in each element of the layout and for each class of vehicle considered (cars, buses and two-axle trucks), in each direction of movement, a minimum sample size of 64 Spot Speed data was used.