Here we have a map of Swanscombe, east of London. Highlighted is the legacy of mineral extraction, infrastructure development and waste management. The blue areas show infilled ground – landfill sites, sand and gravel pits. Red is worked ground. You can see the Swanscombe Chalk Pit here. When it closed in 2008 it had provided 100 million tonnes of chalk to the Northfleet and Swanscombe cement plants. There are also the motorway and railway cuttings. Bottom right is the cutting for the channel tunnel, opened in 2003. Near the Thames – the green area – all that is made ground, embanked and raised. It’s actually mostly fields now, with new houses, and the odd industrial estate and freight harbour. Ignore the grey areas.