The 'Ledo Road' was the Allied supplementary road to the 'Burma Road' (1942/1945).

Named for its starting point at Led in the Indian north-eastern India, the 'Ledo Road' was a vital overland communications link from India to Kunming in the Chinese south-western province of Yunnan, and was constructed to make it possible for the Western Allies to deliver supplies to China.

After the Japanese had cut the 'Burma Road' in 1942, an alternative was required, and this led to the construction of the 'Ledo Road', which was renamed the 'Stilwell Road', after US General Joseph W. Stilwell early in 1945 at the suggestion of Generalissimo Chiang Kai-shek. It passed through the Burmese towns of Shingbwiyang, Myitkyina and Bhamo in Kachin state.

In the 19^th century, British railway builders had surveyed the Pangsau Pass, which is 3,727 ft (1136 m) high on the Indo-Burmese border, on the Patkai crest above Nampong, Arunachal Pradesh, Ledo and Tinsukia. They concluded that a track could be pushed through to Burma and down the Hukawng valley. Although the proposal was dropped, the British assessed the Patkai range for a road from Assam into northern Burma over a distance of 80 miles (130 km). After the British had been pushed back out of most of Burma by the Japanese in the latters' 'B' (iii) operation, the construction of this road became a priority for the USA, which needed an overland route for the delivery of Lend-Lease supplies to China. Rangoon was captured by the Japanese, and before the 'Ledo Road' was finished the bulk of supplies to China had to be delivered via airlift over 'The Hump', as the eastern end of the Himalayan mountains was nicknamed.

Of the road’s 1,072 miles (1726 km), 642 miles (1033 km) are in Burma and 393 miles (632 km) in China and 37 miles (60 km) in India.

On 1 December 1942, General Sir Archibald Wavell, the British Commander-in-Chief India, agreed with Lieutenant General Joseph W. Stilwell, the US commander of the China-Burma-India Theatre of Operations, to build the 'Ledo Road' as a US Northern Combat Area Command undertaking to create the primary supply route to China. Starting from the railhead at Ledo, the road joined the 'Burma Road' at Mong-Yu. From there trucks could continue to Wanting on the Chinese frontier, so that supplies could be delivered to the reception point in Kunming. Stilwell’s staff estimated that the 'Ledo Road' could supply 65,000 tons of supplies per month, greatly surpassing tonnage then being airlifted over 'The Hump'. Brigadier General (soon Major General) Claire L. Chennault, commanding the US China Air Task Force (soon 14^th Army Air Force), thought the projected tonnage levels were overly optimistic and doubted that such an extended network of trails through difficult jungle could ever match the amount of supplies that could be delivered with modern cargo transport aircraft.

The road was built by 15,000 US soldiers (9,000 of them African-Americans) and 35,000 local workers at an estimated cost of US$150 million. The cost also included more than 1,100 US lives, and many of the local populations also died during the construction effort. As most of Burma was in Japanese hands, it was not possible to acquire information about the region’s topography, soils and river behaviour before the start of construction, and such information was gradually acquired as the road was constructed.

Stilwell had organised a Service of Supply under the command of Major General Raymond A. Wheeler, a US Army engineer, and assigned him to supervise the construction of the 'Ledo Road'. Wheeler, in turn, assigned responsibility of base commander for the road construction to Colonel John C. Arrowsmith, who was later succeeded by Colonel Lewis A. Pick.

Work started on the first 103 miles (166 km) of the road during December 1942. The road followed a steep, narrow trail from Ledo, across the Patkai range through the Pangsau pass and down to Shingbwiyang. Sometimes rising as high as 4,600 ft (1400 m), the road required the removal of vast quantities of earth, typically 100,000 ft³ per mile (1800 m³ per km). Steep gradients, hairpin bends and sheer drops of 200 ft (60 m), all in dense rain forest, were common along this initial section. The first bulldozer reached Shingbwiyang on 27 December 1943, three days ahead of schedule.

The building of this section allowed much-needed supplies to flow to the troops engaged in attacking Lieutenant General Renya Mutaguchi’s (from late in 1943 Lieutenant General Shinichi Tanaka’s) 18^th Division, which was defending the northern area of Burma with its main strength located in the areas round Kamaing, Mogaung and Myitkyina. Before the 'Ledo Road' reached Shingbwiyang, Allied troops (most of them the US-trained Chinese divisions of the 'X' Force) had been totally dependent on supplies flown in over the Patkai range. As the Japanese were forced to retreat to the south, the 'Ledo Road' was extended. This was made considerably easier in the stretch from Shingbwiyang by the presence of a fair-weather road built by the Japanese, and the 'Ledo Road' generally followed the Japanese trace. As the road was built, two 4-in (102-mm) fuel pipe lines were laid side-by-side so that fuel for the supply vehicles could be piped instead of trucked along the road.

After the initial section to Shingbwiyang, more sections followed to Warazup, Myitkyina and Bhamo, so,e 375 miles (600 km) from Ledo. At that point the road joined a spur of the old 'Burma Road' and, although improvements to further sections followed, the road was passable. The spur passed through Namkham some 347 miles (558 km) from Ledo and finally at the Mong-Yu road junction, some 465 miles (748 km) from Ledo, met the 'Burma Road'. To get to the Mong-Yu junction, the 'Ledo Road' had to cross 10 major rivers and 155 smaller rivers and streams, averaging one bridge every 2.8 miles (4.5 km).

For the first convoys, a turn to the right took them toward Lashio, some 100 miles (160 km) to the south through Japanese-occupied Burma; and to the left toward Wanting some 60 miles (100 km) to the north just over the China/Burma border. By a time late in 1944, however, the 'Ledo Road' still did not reach China, but by this time the tonnage airlifted over 'The Hump' to China had significantly increased with the arrival of more modern transport aircraft.

Late in 1944, the 'Ledo Road' to the 'Burma Road' though some of its sections beyond Myitkyina in the Hukawng valley were under repair as a result of heavy monsoon rains. The 'Ledo Road' became a highway stretching from Ledo to Kunming, and on 12 January 1945, the first convoy (113 vehicles), led by Pick, departed Ledo and reached Kunming on 4 February 1945. In the six months after the road’s opening, trucks carried 129,000 tons of supplies from India to China. Some 26,000 trucks that carried the cargo on a one-way journey were handed to the Chinese.

As Chennault had predicted, supplies carried over the 'Ledo Road' never approached the tonnage airlifted monthly into China, However, the road complemented the airlifts. The capture of the airfield at Myitkyina enabled the US Air Transport Command 'to fly a more southerly route without fear of Japanese fighters, thus shortening and flattening the Hump trip with astonishing results.' In July 1943 the air tonnage was 5,500 rising to 8,000 in September and to 13,000 in November. After the capture of Myitkyina, the deliveries jumped from 18,000 tons in June 1944 to 39,000 tons in November 1944. In July 1945, the last full month before the end of World War II, 71,000 tons were flown into China, while only 6,000 tons were delivered along the 'Ledo Road'. The airlift operation continued until the end of the war, with a total tonnage of 650,000 tons compared to 147,000 for the 'Ledo Road'.