The city of Auckland was founded in 1840 in a mix of hope and compromise and the occasion was marked with a suitably pompous ceremony. Just one eyewitness account remains from that day, and it was written by the only Pakeha woman present.

Sarah Mathew was born in London in 1805, and for ten years worked as a governess. In her late 20's Sarah agreed to marry her cousin Felton Mathew and follow him out to Australia where he had obtained a position as a surveyor. He left for Sydney in 1829 and two years later, Sarah followed - the first of a remarkable six journeys she made between Britain and the southern hemisphere, all the more impressive when you learn that she suffered terribly from sea sickness. She arrived in Sydney in January 1832, married Felton and then almost immediately went with him on his long surveying trips into the bush.

Author Tessa Duder has written a biography of Sarah, drawing upon the journals and diaries she wrote during her long life in the colonies and back home in England. She believes Sarah would have assisted Felton with the hard physical work of surveying and shared his hardships under canvas in the baking New South Wales sun.

'The extraordinary thing is, she kept the diaries. She wrote the books day in and day out.'

Sarah and Felton suffered two stillbirths while in Sydney and in her journals there are hints of other misfortunes. This was the start of a run of mixed luck for the couple. Felton lost his job in 1839 due to disagreements between Sydney and London over which had the power to make civic appointments. He was quickly shoulder-tapped by William Hobson to help found the planned colony of New Zealand and to advise on the location of a capital city.

Felton sailed to the Bay of Islands in January 1840 and was present at the signing of the Treaty of Waitangi. Sarah arrived three months later.

I expect we shall very shortly be sent off again to survey and lay out another town in which the seat of government will be fixed. Felton has selected a very favourable situation for the purpose. It is to be called Auckland.

For two months on a tiny boat, Sarah and Felton sailed and surveyed from Northland to Thames, climbing seemingly every mountain and exploring rivers, streams and harbours. Despite some initial misgivings on Felton's behalf, a site on the Waitemata harbour was chosen and on September 18 1840 a ceremony was held to mark the founding of the nation's new capital. Sarah was the only Pakeha woman present on shore and typically, she wrote it all down…

Go to this episode on rnz.co.nz for more details