• Roman builders worked the stone at Barnack.
• In the Saxon period religious houses used the stone to build churches in the area.
• In 1185 Ramsey gained the rights to quarry at Barnack.
• In 1335 the monks of St Edmunds leased the quarry.
• In the 15th century Walcot Hall was partially built using stone from the neighbouring quarry.
• By the start of the 16th century the quarries were likely to have been exhausted.
• What is left is an uneven and rugged surface covered by limestone grassland. It is owned by the Burghley Estate Trust and leased in 1976 to Nature Conservancy Council. A quarter of the site is sub-leased to the Northamptonshire Naturalists' Trust.
• It is now a National Nature Reserve managed by Natural England.
• In 2002 it was designated as a Special Area for Conservation to protect the orchard rich grassland.

Architecture:

The stone that was quarried from the site is called Barnack Rag. Barnack Rag is the oldest well-known building stone of Northampton and it constitutes a portion of the Lincolnshire Oolite series.

It was originally limestone from Jurassic Times. It is made from the remains of billions of tiny sea-creatures, cemented together by carbonate of lime. They came from a warm shallow sea that covered this area 150 million years ago. It is coarsely-bedded and may be between 0.9 - 1.22m (3 - 4ft) thick, in blocks of 9 square meters (30 cubic ft), weighing up to two or three tons. The size of the site is 22 hectares (54.36 acres).

The upper stage is open, standing on a moulded weathering with battlement transoms. On top of this is a richly carved cornice with carved pinnacles at each angle and a slender spire surmounted by a Maltese cross. The main material used is Clipsham stone and the 3 steps at the bottom were made from patent Victorian stone.

Social history:

It is thought that the stone was used for the foundations of Medeshamstede.

The stone was transported on sleds to the River Welland or River Nene and loaded onto barges which were then transported inland to be used by the religious houses. The Barnack Rag was used to build the major Abbeys of Peterborough, Ely, Thorney, Crowland, Ramsey, Sawtry and Bury St Edmunds, and the monasteries frequently fought over the rights to it. At one time the quarries were the largest of any inland place in the kingdom.

It is called Hills and Holes because the 'holes' are where the old quarries followed good bands of stone; while the 'hills' are spoil heaps. With over 4 centuries of natural colonisation it has been turned into one of Britain's most important wildlife sites and is home to 8 species of orchids. The rarest plant that is found there is the pasque flower.