A Trip to Castle Hill - Part 1

A view of Castle Hill from the south-west

Following my day out to the Yorkshire Sculpture Park, my next trip with the Sheffield U3A Geology Group involved an exploration of Castle Hill – a distinctive landform to the south of Huddersfield, which has been occupied many times since an Iron Age fort was built here and it is now protected as a Scheduled Ancient Monument.

The geology around Castle Hill

I first saw this very impressive place from afar, 3 years ago, when exploring the nearby Beaumont Park but, currently being limited to public transport in my travels, I didn’t think that I would be able to visit it. Castle Hill is formed by a succession of alternating sandstones and softer siltstones and shales within the Greenmoor Rock - familiar from previous visits to Green Moor and Brincliffe Edge - which dip to the north-east and looking at it from a distance, various benches can be determined in its slopes. 

A discussion at the base of the Victoria Tower

In the absence of our official leader for the day, Chris Darmon, who had led us around Alderley Edge the previous month, 20 of us gathered at the base of the Victoria Tower to escape the strong wind before starting on what was effectively a self-guided walk – following the Green walk that is detailed in a comprehensive Geology Trail produced by the West Yorkshire Geology Trust. 

The Green walk - reproduced from the Castle Hill Geology Trail

Heading south-east down from Castle Hill, the first stop was to examine a section of dry stone walling that was built originally from the local flaggy Greenmoor Rock, but which has been subsequently extended or rebuilt using larger blocks of yellowish coloured sandstone. This has the appearance of Grenoside Sandstone, the next highest rock in the geological succession, which I had seen before in Grenoside village and at Norton in Sheffield. 

Examining the dry stone wall on Lumb Lane

In addition to containing at least three varieties of sandstone, this section of walling on Lumb Lane also contains both red and grey granite, in the form of setts that were once used for road surfacing and which have now been recycled, and possibly basalt – although an examination of this with a hand lens proved inconclusive due to the highly weathered surface, which revealed no obvious feldspar or pyroxene crystals. 

A recycled grey granite sett among various sandstones

The walk then continued past weavers’ cottages, where the pattern of upper floor windows provided evidence of their former use, and then continued across the 80 Yard Rock where faults are marked on the geological map, but which didn’t prove easy to positively identify amongst the landforms seen here. 

The Millstone Grit moors with the Meltham syncline to the right

Continuing down through the geological succession, where 5 coal seams are found, old workings at the surface are marked by the presence of a pond and a gorse covered waste heap; however, the group struggled to find them and we decided to stop for lunch at a point where we had views of the Meltham syncline on the skyline and from which the Crosland Hill sandstones quarries – used to supply many projects in Sheffield – could also be seen.

A distant view of the Crosland Hill Quarry