Irchester Country Park contains Jurassic limestone dating from around 165mya. It is overgrown in places and can be rocky or flooded, with a constant danger of rock falls. This means this site is unsuitable for children.
♦ From the A509, at the Wilby Way roundabout, take the second exit onto the A45. Leave the A45 at Junction 14 and take the second exit of the roundabout back onto the A509.
♦ At the next roundabout, take the third exit and remain on the A509.
♦ At the following roundabout, take the first exit onto Gipsy Lane and then follow signs to Irchester Country Park.
♦ For SatNavs, use NN29 7DL.
♦ Ref: 52.283761, -0.666851
FIND FREQUENCY: ♦♦♦ – Fossils can be found by examining fallen blocks of limestone on the quarry floor. Specimens can be quite hard to find if there are no such fallen blocks, but there is usually something to be found, as the rock faces are unstable, due to constant erosion, in particular, from flooding.
CHILDREN: ♦♦ – This site is not really suitable for children, due to the quarry having a very steep walk down to it and the constant dangers of rock falls. However, there are toilets and a cafe onsite at the park.
ACCESS: ♦♦♦ – There is pay and display car parking at Irchester Country Park. As you drive into the car park, on the right hand side there is a sign with pictures of the fossils that can be found here. Next to this sign, on the left hand side, there is a walkway. Follow this past the overgrown areas of the quarry, until you see the massive rock face of the Wembley Pit. Here, you will see a way down, which is fairly steep but manageable.
TYPE: – This is a disused ironstone quarry. Fossils can be found in fallen limestone blocks and in any loose rocks on the quarry floor. You are free to collect fossils and visit this location. However, note that Irchester Country Park is a Regionally Important Geology Site (RIGS) and a unique setting. As such, you must inform park rangers of your intention to visit by phoning 01933 276866 in advance.
All the best fossils have been found in fallen Limestone blocks, which can be full of brachiopods and bivalves. Ammonites, fish teeth, corals and nautiluses have been found. You can also find sea urchins, gastropods, brachiopods, ammonites and bivalves, with brachiopods and bivalves being the most common. In addition, you can sometimes find brachiopods and bivalves loose on the ground.
The country park is situated on the site of an old sandstone/ironstone quarry. The iron ore (referred to as ‘Northampton sands with ironstone’), which was up to 7m thick in places, underlies a succession of sands, clays and limestone, amounting to a depth of about 16m. These strata are all Jurassic in age, being laid down about 150mya. The sand was deposited under the sea during the Bajocian stage of the Middle Jurassic, dating back about 165myrs. It is overlain by limestones and mud rocks, which can be found lying in the quarry.
If using a hammer and chisel, you will need safety goggles. A hardhat and walking boots are also recommended. Beware of the steep walk down into the quarry. In addition, there is no phone signal once you are there, and there are regular and dangerous rock falls.
The only tools you will need are a handheld magnifying glass, walking boots and a mobile phone.
This site is owned by the Irchester Country Park, you are free to collect fossils, but the use of hammers or striking tools will need permision by the country park.