Where are the boulders today?

And where were they originally found?

Roland Rockhound's Boulder Hunt

1. In parks and public spaces

2. In gardens

3. Along the edge of fields

4. In banks and beds of streams

5. Hidden in dense vegetation

6. besides roads or publicly accessible railway excavations

7. On roadside verges

8. Hidden in walls or buildings

9. Used to mark estate or district boundaries

10. In churchyards

11. Parked beside trees

Martin's 1890 map shows welsh erratic boulders in an aric from Harborne, Northfield and ROmsley with and extension to Bromsgrove. There are also Rowley Regis boulders spread out to the south and south-east.

Here is a rockhound’s treasure map made by Fred Martin in 1890!

Martin’s map of 1890 shows us that many boulders have been found in the Bromsgrove area, but they occur also in a wide arc from the edge of the Clent Hills through Frankley, and Northfield to Harborne.

This information is plotted on a modern road map further down this page.

The arc in the Northfield areamay represent an “end moraine” – the place where the snout of the glacier paused before retreating. During the pause, the forward movement of ice, would have been balanced by melting of ice, leading to an accumulation of boulders.The lower half of this photograph shows a modern curved end moraine (Tsanfleuron, Switzerland).

Ice came from the right in the year 1855 and stayed until 1860 before retreating. Since then a stream has eroded through it. Many boulders can be seen on the surface of the moraine.

Here all the points from the 1890 map have been replotted onto a modern road map to make it easier to see where they were found. This website concerns the boulders from Arenig and those locally derived basalt (from Rowley Regis) and Coal Measures sandstone which were deposited in one or more ancient ice ages.  The Black Country area to the north-west has granite boulders from Criffel and Eskdale which were deposited in the last ice age. You can find a link to a map of the whole West Midlands here.

The base maps contain OS data © Crown Copyright [and database right] (2022)

Martin's map of erratic boulders in the Birmingham area is superimposed on a modern street map.