Dated 1786, the chart shows Kesters's Docking, Rymes Reedbed etc.
The Great Fen includes a huge area that was once the largest lake in lowland England. In geological terms it did not exist for very long - some 2300 years - but it had a big influence on the culture and heritage of the fens and this part of the country.
You can read about the formation and disappearance of Whittlesea Mere on these four pages.
If you are searching for the site of the Mere today you should not be looking for low-lying areas, as you might expect, but rather for very slightly higher ground. The reason for this strange phenomenon can be found by thinking about what happened to the land when it was drained. The area around the mere had a deep surface of peat and as that dried out it shrank dramatically - as we can see at the Holme Posts. On the other hand the bed of the Mere had a deep layer of sandy silt which had been deposited over hundreds of years. When the denser silt dried out it did not shrink as much so it was left, literally, high and dry as the peat shrank around it.
The main areas of the Great Fen that are thought to have been covered by Whittlesea Mere are now known as Engine Farm, Kester's Docking, Froghall Farm and Old Decoy Farm (see the Project Area Map). Looking east from Trundle Mere Lookout you see what would have been Whittlesea Mere from its western shore.
Click below for a larger version of John Bodger's 1786 chart above and also the chart superimposed on a Google Earth satellite image.