The Cooks River: Australia's sickest urban river is located in the glamorous and famously pretty city of Sydney. This makes sense, given it’s also Australia's largest, hard-surfaced, drainified, leaky-sewered, city. In my little red kayak I decided to trace all 23km of the Cooks River, inspired to do so after paddling my boyhood river over 4 days in the name of Backyard Adventuring. Finding it not only challenging, but shocking in terms of its ill health, I’ve since shifted from wanting to see the wildest and most pristine places on earth, to the most degraded and sick. This is a journey of ill-health, sadness and hope; putting a test to the local saying, ‘if you fall in, you’ll dissolve’.