Photo: Wikimedia CommonsThis Oxfam charity shop in the centre is a treasure trove of secondhand clothes, books and bric-a-brac, with proceeds funding the work of the charity against poverty around the world. Stock changes constantly, so it rewards a regular rummage, and prices are kind. It is sustainable shopping with a social purpose. Dig through the rails for a vintage find, and remember that anything you buy supports a good cause. Discover more of our social impact and sustainable shopping picks.