The new four-lane Highway 69 south of Sudbury (Ontario, Canada) is a model for integrating ecological considerations into highway design and construction. The 10 km section north of Highway 637 that was completed in 2012, includes the first integrated network of wildlife crossings for large animals and reptiles in the province, and its first wildlife bridge. This paper highlights the planning process undertaken for the project, the design details, and the results from 5 years of effectiveness monitoring of the mitigation system for large animals. Post-construction monitoring continues to highlight the successes and challenges of the mitigation system, and ensures that design modifications are implemented into new construction contracts as the highway expansion continues. The goal is that the eventual 140 km of newly expanded four-lane highway will form the most extensively mitigated freeway in the province for large animals, and endangered turtles and snakes.