One of the oldest windmills in the UK is at risk of collapse, we are working to save it.

Bourn Windmill is located between the villages of Bourn and Caxton, just south of Cambourne. It was purchased by our charity in 1936 and restored from a state of dereliction into working order.

Watch the video below to learn more about the Bourn Windmill project with Graham, one of our Mill volunteers. 


The Windmill dates from before 1636. It is an open trestle post mill, which means that the whole mill rotates around a central pole. There are only around 50 of this type of extraordinary windmill remaining in the UK, 5 of which are in Cambridgeshire. Much of the mills' interior and workings are original with numerous names and dates carved onto the woodwork. In recognition of its heritage value to the nation, the windmill is designated as an Ancient Monument and is Grade I listed.

Graham Bruce is one of the CambridgePPF volunteers who helps to maintain the mill, “during a routine inspection in 2020 we found evidence of rot in the cross beams. It is the beams that help support the weight of the mill and so this was a bit of a concern, so the charity contacted Historic England for help. They provided advice and an emergency grant to pay for a structural engineer and Millwright to carry out investigative surveys.”

In June 2020, they started removing the bitumen that protects the woodwork in order to assess the extent of the rot. What they found surprised and concerned them, as Bill Griffith’s, the Millwright describes “a sand and cement material, which we had imagined had been used only in a limited way as a filler for small defects, was actually extensively distributed in the centre of all four crosstree arms. The wood surrounding this sand and cement material showed rot in several places and it appeared that rainwater was infiltrating the structure of the crosstree arms". The mortar was used for repairs in the 1980s when rot was discovered. These repairs are now over 35 years old.

The conclusion was a risk that the beam could fail and the mill could collapse. It was considered that it was not safe enough to complete the investigative surveys and they have recommended that the mill is made safe by scaffolding/propping. This would also enable them to complete their surveys and assess the extent of the damage. It should then be possible to design a scheme of repairs in order to secure the future of the mill.

The mill is now closed until further notice, although it can still be viewed from nearby. The mill has been placed on the “Heritage at Risk Register” by Historic England.

The cost of scaffolding and propping the mill for a year is around £12,000 and we need to do this as soon as possible but we also need to employ an experienced conservation architect and project team to assess the damage and design repairs. Only at that stage will we know what the costs of repair might be. The total project costs are likely to be in the region of £50-100,000, so we have launched a major fundraising appeal. You can help by donating via the appeal below.

We will provide regular updates on the project below:

September 2020

We are delighted to have been awarded a grant of £23,250 by Historic England towards the £33,000 costs of the first phase of the project. This will help pay for scaffolding and propping the mill and enable us to employ a project team to assess the damage and design a scheme of repairs. It will also provide employment for skilled conservation professionals during the Covid pandemic.

However we still need to raise another £10,000 for this first phase of the project. We are delighted that members of the public have donated £2,000 so far. Please help if you can, every little helps.

Please continue to follow this page for updates and progress reports on the Save Bourn Windmill project.