A BLACK door, filthy from decades of roadsplash grime, opens directly from the street. On one side of it is a pizza shop; on the other a couple of kebab takeaways, and the downcomer beside it has rusted away at headheight so that when it rains, the water must splurge out onto the pavement.

The fanlight above the door is so encrusted with dirt that no light filters into the narrow dark passage behind. The passage leads straight to another doorway which opens to reveal complete blackness. I pull out my phone and turn on the flashlight only to discover that I’m wrapped up in a straggly curtain of thick spiders’ webs. Behind the curtain is gloryhole of junk in an understairs cupboard.

I manoeuvre out, brush off the dust of ages, shut the door, and turn and follow the passage further back.

The Northern Echo: Peases house Picture: SARAH CALDECOTT

It passes a once elaborate doorframe which is now painted a turgid dark brown and is breeze blocked up so I can’t break into the pizza parlour next door.

At the back of the property, a mid-Victorian staircase with a wobbly handrail leads up to the first floor where a lose floorboard threatens to plunge me back to the ground.

Everything movable has been ripped out, leaving the ghostly outlines of lost fireplaces and stolen skirting boards, and on the walls there’s just a hint of where a dado rail once ran. Bodged into the bare brick wall is a modern tripartite window, echoing the original wooden one and giving views over a tarmac car park towards some warehouses on the banks of the River Skerne.

The Northern Echo: Peases house Picture: SARAH CALDECOTT

It lets light flood into the ruined room, revealing the great gaps in the ceiling and the rafters at the top of the third storey.

The light also picks out the remains of a plaster cornice running around the edge of the ceiling. Quite an elegant cornice. Probably a Georgian one.

Suddenly, I am transported back 200 years to when the cornice was clean, when a freshly painted dado rail ran around the wall at waistheight, when a fire roared in the grate and when out of the window, instead of a car park, there was one of Darlington’s finest gardens, full of fruit trees and a little bridge over the river…

The Northern Echo: Peases house Picture: SARAH CALDECOTT

Back to when Edward Pease lived in this house on Northgate – perhaps this was his bedroom.

Back to when, on April 19, 1821, he was upstairs on this floor when George Stephenson turned up at the front door – somewhere near the dirty black door – and was ushered into the ground floor kitchen in what is now a kebab shop. That, as Memories told a fortnight ago, was a meeting that changed the world as Stephenson persuaded Pease that steampower, and not horsepower, should be the motive force on the planned Stockton & Darlington Railway.

Darlington council has just acquired this derelict building, which is the central part of Pease’s house, through the Government’s Towns Fund. The first job is to stabilise and secure the building which has been occupied only by pigeons for at least the last 30 years.

The Northern Echo: Peases house Picture: SARAH CALDECOTT

The next step will be to work out how it, perhaps augmented by the future acquisition of the wings on either side, can be used to benefit the community – residential, retail, public space or a heritage interpretation in time for the 2025 bicentenary.

“It is terrific to find this much is still here – there’s far more than I expected,” said Matthew Pease, the great-great-great-great-grandson of Edward, who Memories accompanied earlier this week on a first trip into the dereliction. “With what we know and what we can see, we can recreate these rooms so that someone who came to the house in the 19th Century would recognise them.”

Edward bought the property for £600 on November 6, 1799, and the earliest parts of it seem to date from at least the 1750s.

The Northern Echo: Peases house Picture: SARAH CALDECOTT

It was then the last house in town, and he was a prosperous 32-year-old woollen merchant, married to Rachel with three very young children – Joseph, whose statue now stands on High Row, can only have been a month or so old when the family moved in.

For the next 59 years, this was Edward’s home and the scene of all of his domestic landmarks.

It was here that Rachel bore their next five children; it was here that Stephenson came practically every night in the early 1820s to inform Edward of progress on the railway; it was here that Edward spent the railway’s opening day – September 27, 1825 – in mourning for his favourite son, Isaac, who’d died that very morning, in one of these rooms, of tuberculosis at the age of 19.

The Northern Echo: Peases house Picture: SARAH CALDECOTT

It was here, in the kitchen which is now the Best Kebab 1, that Rachel handwrote her cookbook that Memories serialised about 10 years ago, and it was here that she and Edward entertained.

“Edward kept an excellent table, with good quality linen, china, silver and glass,” says Anne Orde in her 2000 study of the Pease family. “He was not a teetotaller: beer was always provided, and after the white tablecloth was removed, heavy cut glass decanters of madeira, port, and two other kinds of Portuguese wine were put on the table with the fruit from the garden that formed the dessert.”

The Northern Echo: Peases house Picture: SARAH CALDECOTT

That garden is now covered by the Garden Street car park, but it once had an ornamental area where Edward walked, perhaps accompanied by his “black dalmatian dog”, looking at his feature sundial, resting beneath the largest acacia tree in Darlington and admiring his fruit cages from a little pagoda.

In those cages grew vines and figs, plus peaches, nectarines, cherries, apricots, plums, pears and several varieties of apple.

A footpath wended its way past them to a bridge over the Skerne which joined his garden with that of his eldest son, John, who lived in the now demolished mansion of East Mount on the opposite bank of the river.

It was in this house that Rachel died, aged 64 in 1833, leaving Edward alone for the remaining 25 years of his life (although the 1841 census has him living in the house with three female and one male servants). He probably didn’t update the house or gardens after she’d gone, instead becoming the introspectively devout and grumpy old man that we can see in his own pen in his diaries from his later years.

And it was here that he died, aged 91, on July 31, 1858.

The Northern Echo: Peases house Picture: SARAH CALDECOTT

Almost immediately, the house was sold and in 1866 a mock classical frontage was clagged onto it, hiding Edward’s plain Georgian townhouse, as it was converted into retail units. Tailors, drapers and butchers used to occupy it, and now it is home to the takeaway makers.

So disguised was it that Darlington lost contact with its history and its direct connection to the birth of the railways.

If any building can be said to have changed the world, it is the one hidden behind the black door and the roadsplash and the grime of time.

Perhaps for the bicentenary, its dereliction will have been cured and it can play a key role in telling the story of the railways it helped to create.