From a Wikipedia article about the Mangapurua Valley:
THE BRIDGE TO NOWHERE
Started in January 1935 and completed in June 1936, this bridge was built by the Raetihi firm of Sandford and Brown, for the Public Works Department. It is 130 feet long, and 125 feet above the stream. The cost of labour was 598 pounds 11 shillings 7 pence, and cartage of all materials (via the Mangapurua Valley road) cost 419 pounds 14 shillings. Unfortunately the cost of materials was not recorded. Aggregate for the concrete is said to have been transported from the Rangitikei River. The completion of the bridge was delayed considerably due to floods, slips, and the consequent delay in the supply of materials. The bridge was built to facilitate vehicular access to the Wanganui River, to link the settlers of the valley with the riverboat service. In 1917 the Government opened up the valley for settlement by soldiers returning from World War I. Virgin forest was cleared, and a total of 35 holdings developed. A school was opened, and for some years the valley prospered. However economic hardship, and problems associated with the remoteness and difficulty of access, resulted in many families abandoning their farms. By 1942 there were only 3 families left. After a major flood in January 1942 the Government declined to make further funds available for road maintenance, and it officially closed the valley in May 1942. The disappearing road line, old fence lines, stands of exotic trees, occasional brick chimneys, and this bridge serve as reminders of the ill fated settlement of the Mangapurua valley.
Today’s ride was by no means easy, but certainly easier. From Cootes Clearing the track followed a quad bike track most of the way to the Bridge To Nowhere. For the 10 hours it took me to get there, I could cycle about 40% of it. The rest was pushed, carried, and hauled.
The photo above shows a rare smooth section of bare sandstone rock near Cootes Clearing. This mostly cycle-able track led all the way up to the Mangapurua Trig.
Arrival at the top of the ridge was a big milestone, because from here it was all downhill. No more grunting and pushing.
My optimism was short-live however. The track disintegrated into a deeply rutted 4×4 four wheel motorbike track.
This lasted for two hours, before the deep gullies cut by streams flowing into the Mangapurua Stream put a stop to the quad bikes’ progress. They slowed me too, forcing me to remove all my luggage from my bike every time I had to cross a swing bridge.
After the fifth time-consuming crossing, I took to just lifting the whole bike up and over the wooden poles at the beginning of the bridge. I could then wheel the bike across, nervously making care not to drop the wheels off the side. Hoping that the bridge (limit one person) would carry the combined weight of me and the bike.
If swing bridges and muddy quad bike tracks weren’t enough, the other challenges were the bluffs. Many of these massive cliffs with their precarious tracks were washed out in places. Ferrying my gear and bike across these washouts, my heart was in my throat.
I arrived at the Bridge To Nowhere well after dark. I had hoped to get all the way to Mangapurua Landing on the river, but that was not going to happen tonight. I camped on the bridge instead, since it would not do not to take photos of this phenomenon of mad gonvernment planning.