European hedgehog (Erinaceus europaeus) populations have declined by 30-50% in the UK since 2000, with road mortality identified as a leading cause alongside habitat loss and garden fragmentation. Hedgehogs travel 2-3 km nightly in search of food and mates, crossing roads repeatedly. Research estimates 100,000-300,000 hedgehogs are killed on UK roads annually. Welfare implications are significant: road strikes cause traumatic injury, with survivors frequently requiring rehabilitation. Urban garden connectivity - via 13cm holes in garden fences - allows hedgehog movement without road crossing. Wildlife crossing structures (tunnels, underpasses) beneath roads have proven effective in reducing road mortality in trials. Monitoring programmes using footprint tunnels and GPS tracking inform urban planning and road mitigation strategies. The People's Trust for Endangered Species Hedgehog Street campaign has created over 100,000 garden highway links.