A desire path exposes the intricate root systems of ground cover at the northern end of Hyde Park in Sydney. According to 99% Invisible it can take "as few as 15 traversals" to begin a desire path - depending on weather conditions and the environment.
Sometimes, high-traffic desire paths are taken into account in city planning. I watched a while people navigated the park landscape. Backpackers flicked coins into the Archibald fountain while business people hurried in the lunchtime rush, shaving a few seconds off their commute by taking this well-established route.