Venice Secondary Highways is a line theme representing Road Network features in Venice based on the "Functional Class" value on each link present in NAVSTREETS. This layer contains all links that have a "Functional Class" value of 'Level 3' and 'Level 4'. Functional Class 3 roads interconnect Level 2 roads and provide a high volume of traffic movement at a lower level of mobility than Level 2 roads. Functional Class 4 roads provide for a high volume of traffic movement at moderate speeds between neighborhoods.