Steeps › The 2019 Guinness record: Harlech vs Dunedin
The 2019 Guinness record: Harlech vs Dunedin
In 2019 a short street in North Wales was named the steepest in the world. Less than a year later, the title went back to New Zealand. This is what happened.
The old holder
Baldwin Street in Dunedin, New Zealand, held the Guinness World Records title for the steepest street for over a decade, until mid 2019.
July 2019: Harlech takes the title
From 15 July 2019, Guinness World Records named Ffordd Pen Llech in Harlech the "World's Steepest Street". Guinness measured the steepest 10-metre stretch of the street, which has no buildings, giving a tangent gradient of 1:2.73, about 36.6%. UK road signs round that up to 40%. Wikipedia also cites an earlier Guinness-measured figure of 37.45%.
The appeal
Representatives of Baldwin Street appealed, led by surveyor Toby Stoff, and submitted a comparative survey of both streets in three dimensions. After consulting industry specialists, Guinness found what Craig Glenday of Guinness World Records called "a rare gap in our stipulations".
April 2020: reinstated
On 8 April 2020 Guinness reinstated Baldwin Street. It ruled that gradient should be measured along the centreline of the street, and that its guidelines would no longer allow measurements on any other axis. On that basis Baldwin Street measured 34.8% and Ffordd Pen Llech 28.6%.
| Street | Country | Guinness gradient (centreline) |
|---|---|---|
| Baldwin Street, Dunedin | New Zealand | 34.8% |
| Ffordd Pen Llech, Harlech | Wales | 28.6% |
What it means
The Welsh street still has a steep section whose tangent gradient is higher than its centreline gradient. The 2020 ruling does not mean the street became less steep; it means Guinness chose a different way to compare winding or cambered streets. See how gradients are measured for how this works.
Visiting
Ffordd Pen Llech is a public road within Snowdonia National Park, about 0.2 miles long, below Harlech Castle. People live on it, so be considerate. More on the street: Wales. Other steep roads: the ranking.
Why the argument was interesting
It was a dispute about method rather than facts. Nobody claimed the street had been rebuilt. One side measured the steepest short stretch, the other wanted a measure along the centreline that treats winding and straight streets alike. It shows why an apparently simple record, the steepest street, needs a careful rule, and why it is wise to read the footnote whenever a gradient is quoted. For other places where measurement matters, see England and Scotland.
Frequently asked questions
Is Ffordd Pen Llech the steepest street in the world?
Not officially. Guinness reinstated Baldwin Street, Dunedin, in April 2020 under a centreline measuring rule.
When did Harlech win?
Guinness named it the steepest street from 15 July 2019.
What were the gradients?
Baldwin Street 34.8% and Ffordd Pen Llech 28.6% on the centreline method.