Five minutes cycle from the centre of Copenhagen there's an amazing experiment in alternative living. Amongst the lochs, canals and woodland around the old city walls the "free town" of Christiania has grown up on the site of a former army camp. "Hippies" first started to squat here in 1971, and over the years a city-within-a-city has grown up – controversial because illegal dope-smoking is common – and home to 900 hard-working free spirits and their self-built, self-managed and affordable community. Many of the wooden-built waterfront homes are beautiful, with public buildings including a bath-house, concert hall (where Bob Dylan has played), restaurants, cafes, shops, sport facilities, a paddock and artful graffiti. Christiania Bikes are a familiar sight on the streets of Copenhagen. These tricycles with a large box between the two front wheels are great for taking the shopping home (the city's postal service uses 100 for mail deliveries), and parents buy child-carrying versions. Built in Christiania and sold throughout Denmark, Germany and Switzerland, they're also exported to the UK where their environmentally-friendly credentials are a major selling point. Interestingly – just one canal away lies the tiny wooden huts of Vennelyst, the first allotment gardens in Copenhagen opened in 1896 and still going strong today with a massive waiting list. Two very different hutting communities – one very democratic use of prime city centre land.