The Side-by-Side georeferenced site lets you:

Compare a selection of historic maps to a modern map or satellite layers. For DOWHG purposes the best starting point is to compare the OS Six Inch 1888-1913 map with the corresponding modern satellite image. This can show whether buildings still exist or have been altered, etc. It also allows you to see if field boundaries have changed and so on.

How to use it:

  1. When started a help box opens. This is worth reading. Close it by clicking on the 'X' in the top right. If you don't want it to appear again click on bottom right
  2. In the top left hand side click on the 'V' where is says '2. Select a map series'. A menu opens
  3. Click on 'OS Six Inch 1888-1913'. The map appears in the left hand panel. Leave the right hand panel as it is
  4. On the map side slowly zoom in on north Wales using the wheel on the mouse or the '+' symbol (top left). Holding down the left button on the mouse and moving the mouse drags the map around. If you keep a bit of the sea on the left of the map it is easier to see where you are
  5. When you have zoomed in on a house you will see the corresponding satellite image in the right hand panel. The grid reference of where the cursor is is shown at the bottom of each panel.

The Ordnance Survey First Series site lets you:

View OS maps from 1805-1869.

How to use it:

  1. Click on 'Ordnance Survey First Series' to open the maps - the map of Workington in Cumbria opens
  2. Click at the bottom of the small map bottom right to move the image towards Wales. It will take 6 or 7 clicks
  3. When you have found the area you want to look at, hold down the right-hand mouse button and centre the map. Use the mouse wheel or the facility at the top left to zoom in and out.