This is the house where Isaac Newton was born, and where, as a young man, he began the work that changed how humanity understands the universe. Newton was one of the greatest scientists who ever lived. He discovered the laws of gravity and motion, explaining why the planets orbit the Sun and why objects fall to the ground. He invented a whole new branch of mathematics, calculus. He worked out that white light is made of all the colors of the rainbow. His ideas became the foundation of modern physics, and they held for more than two hundred years, until Einstein built on them in the twentieth century. Nearly everything about how we understand motion, force, and the sky above us starts with this man, and this man started here, in a small farmhouse in the English countryside.

We reached Woolsthorpe around one in the afternoon. The village is small, just a few houses on a lane off the A1, surrounded by flat farmland and green fields. This was sheep-farming country in 1642, and it still is. The Newtons were sheep farmers.

The house stands at the end of a short drive. It is a modest farmhouse built of grey limestone, with stone-framed windows and a stone-tiled roof. It is small and plain. It was the home of a well-off farming family in the early seventeenth century, the kind of house owned by people who had their own land and their own flock of sheep. Isaac Newton’s grandfather, Robert Newton, bought the property and its land in 1623. He gave it to his son Isaac as a wedding present in 1639. That son, Isaac Newton the elder, could not read or write, but he was a successful farmer. He died in October 1642, at the age of thirty-six, three months before his only child was born. Above the front door there is a stone plaque with the Newton family coat of arms, recording the birth of Sir Isaac Newton on 25 December 1642.

Newton was born in this house on Christmas Day 1642. He was born early and was very small. His mother later said he could have fit inside a quart mug. No one expected him to survive. His father had already died. When Newton was three, his mother married again, to Barnabas Smith, a church rector in a village a mile and a half away. She moved there and left Newton at Woolsthorpe to be raised by his grandmother. Newton was angry at both of them for this. Years later, at the age of nineteen, he wrote a list of his own sins. One of them was: “Threatening my father and mother Smith to burn them and the house over them.”

We went inside. On the ground floor there is the old kitchen, with a large open fireplace, and a sitting room with a stone fireplace. This is where the guide told us about Newton’s life, and where copies of his books are displayed. The walls are thick, the windows deep, and the ceilings low. The furniture is not Newton’s own. Almost nothing that belonged to him is left in the house, because much of it was sold off over the years to pay family debts. The National Trust has furnished the rooms with furniture from the correct time period, to show how the house would have looked when he lived there.

Upstairs there are four rooms. One is the bedroom where Newton was born. Another, at the far end, is the room he used during the plague years. It is now called Newton’s Chamber and is set up to look as it would have in 1665. This is the room where he placed a prism in the sunlight coming through the window and split the light into colours. If you stand at that window, you can look down at the garden and the apple tree. In one corner of the room there is a small space closed off with old wooden panelling, which is thought to have been his study. The walls have faint drawings on them, scratched or drawn in charcoal. Newton’s friend William Stukeley, who visited after Newton died, wrote that the walls and ceilings were “full of drawings, which he had made with charcoal. There were birds, beasts, men, ships, plants, mathematical figures, circles, and triangles.” Some of the marks that remain may be Newton’s own. The National Trust does not know for certain which ones.

When Newton was seventeen, his mother tried to make him a farmer. It did not work. Newton hated farming. His teacher at the school in Grantham saw that the boy was talented and convinced the family to let him return to his studies. In 1661 Newton went to Trinity College, Cambridge. He went as a “sizar,” a poor student who paid for his place by working as a servant to the richer students. Nothing about him stood out at the time.

Then the plague arrived. In 1665 it reached Cambridge, the university closed, and Newton went home to Woolsthorpe. He stayed for most of the next two years, about eighteen months, between the ages of twenty-two and twenty-four. He had not wanted to come home, and he later said he was frustrated at being stuck in a farmhouse with no library and no one to talk to. But what he did during those months is remarkable. He worked out the basics of calculus, a new branch of mathematics. He did experiments with glass prisms in his bedroom, splitting white light into the colours of the rainbow, and proved that white light is actually a mixture of all the colours. And he started thinking about gravity, wondering whether the same force that pulls an apple to the ground might reach all the way to the Moon. He later called this his time of greatest discovery. He was not yet twenty-five years old.

The light experiments were done in this house, in his room. But his famous books came later, and were written in Cambridge, not here. His book on light, the Opticks, was published in 1704. His most famous book, the Principia, which explains gravity and the laws of motion, was written in Cambridge and published in 1687, when Newton was in his forties. It took him more than twenty years to turn his early ideas about the apple into the full mathematical theory. Woolsthorpe was where it began, not where it was finished.

Then we went outside to see the apple tree, which has a remarkable history of its own. It grows in the garden, close to the house, and it is the same tree from Newton’s time. It is not a new tree, not a copy, and not grown from a cutting. It blew over in a storm in 1816, but it did not die. It lay on the ground, grew new roots from the fallen trunk, and kept growing. Scientists have confirmed, using tree-ring dating and radiocarbon testing, that this is the same tree that stood here in Newton’s day. It is more than 350 years old. It is a type of cooking apple called a Flower of Kent, and it still produces fruit. The apple tree we saw a few days ago at Trinity College in Cambridge was grown from a cutting of this one. This is the original. The British astronaut Tim Peake took seeds from this tree to the International Space Station and named his mission “Principia” after Newton’s book. We also collected some of the apples on the ground and brought back to the truck.

Beyond the garden, one of the old farm buildings has been turned into a science centre, with hands-on experiments about light, colour, gravity, and motion. It is designed for families and children, but it is based on real science. There is also a secondhand bookshop and a café.

Inside the house, on display, there is a photograph of Albert Einstein’s signature, from when he visited Woolsthorpe. In 1927, on the two hundredth anniversary of Newton’s death, the leading scientists of Britain made an official visit to the house, and Einstein, who greatly admired Newton, took part. Seeing his signature here is a special thing. Einstein completely rebuilt our understanding of gravity, the same subject Newton first worked on in this garden, and he came to this house, the place where it all began, to add his name.

This house came close to being lost. After Newton left for Cambridge, he never lived here again, although he owned the property until he died in 1727. He never married and had no children. The house passed to a distant relative, John Newton, who, according to Stukeley, wasted his inheritance on gambling, horse racing, and drinking, and had to sell it. In 1732 it was bought by Edmund Turnor, a local landowner, who rented it out to a farming family called the Woolertons. They farmed it for the next two hundred years. During those years the windows were bricked up, the rooms were changed, and the drawings on the walls were covered over. The birthplace of modern science became an ordinary farm, and it might have stayed that way, or fallen into ruin.

In 1942, on the three hundredth anniversary of Newton’s birth, the Pilgrim Trust and the Royal Society bought the house. The next year, they gave it to the National Trust. The Trust reopened the bricked-up windows, uncovered the drawings on the walls, and restored the house to look as it did in Newton’s time. It has been open to visitors ever since, and about fifty thousand people come each year, many from other countries.

“Pilgrimage” really is the right word for this place. Einstein visited, and his signature is on display in the house. This is a small stone farmhouse on a quiet lane in the countryside, built by sheep farmers, where an angry, lonely boy who had lost his father and hated farming came home during a plague and, before the age of twenty-five, began the work that would later allow us to understand the planets and travel into space. The rooms are furnished the way they would have been in his time. The fireplaces and windows are the ones he knew. The apple tree is the same tree. The light coming through the bedroom window is the same light he split with a prism. There is very little standing between you and the room where one of the greatest minds in history first began to work.