People had wanted a way up to Mount Spec for decades. Tin had been found west of Paluma in 1875, timber-cutters and farmers wanted access, and from the early 1900s the cool, scenic ranges were promoted as a tourist retreat and a health resort - somewhere to escape Townsville's summer heat. A Mount Spec tin miner named Phillip Foxlee wrote to the Queensland Premier in 1925 describing a gorge "crammed full of waterfalls on every side" and predicting people would come "from all parts of the world." The lobbying ran for thirty years amid genuine controversy over cost and benefit. In 1929 the route was gazetted as one of Queensland's earliest official Tourist Roads, and the long argument finally tipped toward construction.

What pushed the project over the line was the Depression itself, and the government's urgent need to put men to work. Construction began in November 1930 and became the largest Unemployment Relief project in the region. The labour was mostly unskilled - the region's jobless, drawn into isolated camps along the range. Conditions were hard. With only a few trucks, a pair of tractors and two air compressors to help, cuttings were blasted through granite with gelignite while most of the work was done by hand, with picks, shovels, horse-drawn ploughs and scoops. One camp, at The Saddle, housed more than a hundred men for three years; three old ship's water tanks still mark the spot. The job took some six years, and hundreds of men passed through it before the full road opened in 1937.

The bridge over Little Crystal Creek was meant to be an ordinary timber span. The local Main Roads engineers thought otherwise. In June 1931 the District Engineer in Townsville argued that "from the aesthetic point of view a masonry arch should be considered, as it would harmonise with a rather picturesque spot." Brisbane approved the change in 1932, and four stonemasons were brought in to face the concrete arch in dressed stone. It cost more than planned - the District Engineer grumbled in 1933 about "too much work dressing stone" - but the result spoke for itself. The Commissioner of Main Roads called it "an illustration of the high quality of work which can be achieved by such labour skilfully directed." It is reportedly the only stone-faced concrete arch road bridge of its kind still in service in Queensland.

Mount Spec Road still climbs roughly 18 kilometres from the coastal plain to the edge of Paluma, rising some 885 metres up the range. Remarkably, it has never been widened; the original route and character survive, threading the same curves the relief gangs cut by hand. Along the way the same craftsmanship repeats in smaller forms - dry stone walling, stone-paved gutters, and a string of little concrete arch culverts built in the bridge's image. The road opens onto sweeping views of Halifax Bay and the coastal plain as it twists upward, and at the bottom of the gorge Little Crystal Creek still tumbles past its arch into the clear pools below, a swimming hole that remains one of Townsville's favourite escapes.