Coombs quarry is located just off the A421 between Buckingham
and Milton Keynes. It was a working quarry up until the end of the
19th century. There are the remains of some lime kilns close by.
The stone here may
have been quarried since at least Roman times. The local
medieval Thornborough bridge was certainly made from the local
stone.
Coombs quarry is the site of an excellent exposure of Jurassic
limestone. The Jurassic period lasted, roughly 55 million years,
between 199 to 164 million years ago. These, particular layers of
sedimentary rock, are known as Blisworth limestone, and run as a
ridge, from Lincolnshire to around Bath.
There are 2 possible
parking locations. The one I would recommend is at
Thornborough bridge, where you can view the bridge itself and
the Romano-British burial mounds.
Recommended parking at N51 59.535 W000
56.282
If you follow the footpath signs and cross the A421 you can walk
across the fields. Cross the stile where the path splits and walk
south directly over the field. Go over the little bridge and across
the next field. Before you go through to the next field turn left
through another gate and the entrance to the quarry is in front of
you. Please note! Sometimes the brook is in flood and the route is
impassable. Alternative parking is detailed below
The second parking is in the Thornborough Community Woodland car
park. N51 58.942 W 000 55.966. You
cross the road, go through the gate and follow the footpath that
runs parallel to the road. If you bear left around the building the
path opens out opposite the entrance to the quarry.
Please don't park in the entrance to the quarry, or along the
roadside.
You are looking for a regular sized boxed, camouflaged to blend
in.