A brief history of the Area from 150 million years ago to the present day!

Approximately 150 million years ago, the Kimmeridge Clay, which is the underlying rock throughout the Area, was laid down as a very fine sediment on a former sea bed here, when the climate was much warmer than it is today. Kimmeridge Clay is not specific to Horspath, but extends from Dorset right across England and into the North Sea, where it is the source rock for the oil fields. Later geological uplift, slight tilting of the strata, and subsequent erosion of this former sea bed, has exposed the clay here as the lowest and impermeable layer of the geological ‘sandwich’ of clays and sands which make up the underlying rocks of Shotover Hill and Horspath Common. As a result, many small intermittent streams have emerged from the clay in Horspath since the end of the last Ice Age approximately 10,000 years ago, to drain away the rainwater which today percolates down through other permeable overlaying rock strata higher up the hill.

The original forests of Oxfordshire were progressively removed as agriculture was developed by early settlers from about 5,000 years ago, and the Romans certainly cut wood to fire pottery kilns in this area as early as 1,900 years ago. More recent documentary evidence indicates that a protected Royal Forest on Shotover extended as far as the edge of Horspath from before 1066 until 1660, after which it was privately owned and split up.

In approximately 1860 this railway cutting and the tunnel through the hill were dug out to create a railway link between Oxford and Marylebone Station in London, via Thame and Princes Risborough. Railway trains used this cutting until 1963, when all such branch lines in England were abandoned, and so the present woodland, which grew up on the site after the railway line was closed, is mostly only 40 years old, and is still developing.

The railway builders installed drains in the tunnel, and beside the track through the cutting, so that today these same drains deliver water into one of the ponds, and carry away any flood overflows from the others. Additional twin drainpipes were installed in the bottom of the cutting as flood drains in about 1980, after a minor landslip had occurred on the north-west side of the cutting. The site was purchased by Horspath Parish Council for £700 in 1982. There were some attempts in the 1980s to manage the cutting as a nature reserve, but Nature won that battle, and it had become very seriously overgrown and impenetrable by 1999. The Council received £4,950 of Lottery money as a Millennium Festival Award in 2000, and this money was used to fence the site, to terminate its use as an informal rubbish tip, to clear all the bushes and brambles from the valley bottom, and to lay a 400-metre-long gravel access path. Subsequent grants from The Friends of Horspath and S.O.D.C. in 2001 and 2002 have paid for the construction by local volunteers of three ponds, a log pile footbridge across the stream, bird nesting boxes, and the purchase of tools and the hire of equipment to be used by the village volunteers for further conservation management.