English Settlement

 The English Landscape and Identities Project has some tri-variate maps of England showing eras of archaeological sites. The author, Chris Green, begins with an apology to those with color deficiencies. Because three color channels are needed, it would be hard to make this more legible to color blind readers*. The legend is shown first to see what you are looking at.

Darker areas are more "complex" - meaning there are sites from more time periods. The primary colors show more specific time periods as seen above. Magenta is Roman in case the image is hard to read.

There is a second map based on more local variation on the blog post, but I find this one easier to interpret. Some of the patterns that show up are settlement along Roman roads (magenta lines), some clusters of prehistoric sites in the southwest and northeast and a much lower level of intensity in the west (fewer archaeological sites here?) Some of the darkest, most intense areas are along major river valleys where quarrying activities have possibly uncovered more sites than average.

This map is based on available data and may not tell the full story but it does give an idea of the variation and complexity of archaeological records.

* This color scheme (via StackExchange) would have worked for color deficiencies.