A method, a system, and a computer program product may be provided for generating at least one route speed funnel for roadwork zone identification. The method may include generating a plurality of learned road signs from a plurality of road sign observations captured by a plurality of vehicles, determining a plurality of primary speed funnels, and generating at least one route speed funnel from the plurality of primary speed funnels based on a route validity condition. Each of the plurality of primary speed funnels comprises a different pair of learned road signs selected from the generated plurality of learned road signs. The method may further include determining a plurality of candidate speed funnels and temporally validating the plurality of candidate speed funnels to obtain the plurality of primary speed funnels.