The Siltorn Canal in Ororr is a pioneering system of canals and locks which links the heartlands of the Wiyel Basin with the northwestern provinces, which are otherwise isolated by the Siltorn Highlands. The key link in the network is a series of canal tunnels running through the mountains, raising barges and lowering them to the far side. The Siltorn Canal is a critical link in Ororr's internal trade network, since trade was previously possible by pack trains over the treacherous highland passes, or the long way around the coast from Toborr.
From the foundation of Ororr, the capital was established in the west, in the homelands of the former Mordant empire where the people were absolutely loyal to the future of the State. However, the Prophet built his home and formalised his new religion within the bounds of the old Empire. After His departure the old Mordant guard remained suspicious of the decadent East and kept their ideological capital in the west, in the labyrinthine administrative city of Toruor.
As the nation grew, this division caused increasing tension. The religious centres, places of the greatest miracles and triumphs of the Prophet, were in the east, yet the administrative and military homeland was in the west. (In actual terms the Prophet cared little for the violent tribes of the west, whom he had merely used as muscle for his conquest of the crumbling EnSanni imperium.)
The problem was exacerbated by geography. The Wiyel basin, essentially the old Empire, is separated from the west coast by the Siltorn uplands. Boats could only travel reliably as far as the great lakes above Initerra. Thereafter the rivers were rapid and not navigable. Beyond Initerra, all goods and travellers went onward by road and portage, with great trains travelling up mountain passes, descending on the western side via precipitous paths, plunging down to the valley floor below.
Travelling over the mountains was hair-raising and slow, and many preferred to travel by sea. However, Ororran ships had never been reliable and the EnSanni had superstitious fear of the sea. Sea-going ships were little more than converted river galleys, that hugged the coast and had to flee safe anchorage at the first sight of rough weather. Ships were often lost.
The geographical divide rapidly became a political one in the first hundred years of the Mother State. Once the economy recovered in the shattered former empire, most commerce was done in the vibrant east. All the richest cities were former En-Sanni ones, and the River Wiyel itself was the heart of pilgrimage to Foratuna. There were severe pressures from the newly converted EnSanni elite to move the capital to somewhere in the east, such as Remel, both the site of the Prophet's first great victory against the EnSanni, and a city centrally located on the Wiyel.
The old Mordant priest-militant guard viewed this with absolute horror, and the fragile government established by the Prophet never looked more tenuous. Within twenty years of the Prophet's ascension, Ororr threatened to fragment once more into east and west. The Mordant military command maintained a dominance bordering on a military coup.
Scouring the archives for a solution to the problem, the old guard discovered plans that had long lain in the planning archives of the old Siltorn Republic. They had been devised centuries ago as an effort to boost the flagging economy of the Sixth Republic, but had been shelved as a ridiculous and dangerous extravagance. Siltorn engineers had proprosed uniting themselves with the city-states on the Torl river against the Mordants by building an elaborate network of canals, tunnels and elaborate sluices, enabling ships to travel through the mountains.
The Ororran government diverted the vast financial resources of the new empire into the project, the hope of uniting the two halves of the Mother State.
The first stage involved building canals with a series of locks, up to the lowest pass of the western heights. The canals were fed by diverting hundreds of smaller streams, building huge reservoir lakes high in the mountain plateau.
The second stage was the most ambitious. Engineers built a complex series of tunnels and water-lifts right through the mountain. Long tubes of canal tunnel ended with wide shafts, with water-tight locks at the bottom, made of strong steel bulk-heads - themselves miracles of metallurgical engineering. A barge would pass into the mountain and enter a lift, full of water. The lower doors would gradually open, water would flow into the tunnel below, lowering the ship down to the next level. The flow of water would also propel vessels in the lower tunnel up to the next level.
Ororran engineers also added another innovation. Floats and chains in the shafts would rise as the shaft was filled. The end of the chain could be hooked to an upcoming barge, pulling it along the lower tunnel.
The great mountain lift system consisted of eighteen vertical shafts and linking tunnels, flowing out into an artificial lake on the valley floor on the Torl side of the mountain. Thereafter it was a comparatively simple progression through locks on the Torl river, down to the river cities.
Ironically it was construction on the Torl side that caused the most difficulties and controversies. Money ran out, and two catastrophic shaft failures in the mountain flooded the works on the far side, destroying the river-workings, destroying the lower shaft-locks and causing massive floods in villages all along the valley.