Cable Transport: Development Prospects and Application Opportunities

Intensive urbanization in today’s world is marked by numerous challenges. As the population of megacities continues to grow, so does the number of personal vehicles, leading to increased traffic congestion. In such conditions, alternative solutions must be explored—particularly by utilizing the untapped space above the ground. Cableways and modern string transport systems (uST technology) are ideally suited for this purpose. Below, we’ll examine the origins of these technologies, their evolution and technical similarities, as well as their future potential.

History and Evolution of Cable Transport

A cableway is a type of transport that uses cable traction to move. It carries passengers and cargo in special cabins known as gondolas or carts. Its predecessor was likely rope transport, with depictions dating back to 250 BCE in southern China. The first design of suspended transport is credited to Venetian engineer Fausto Veranzio, whose mechanical cableway drawings date to 1616. A working prototype appeared later in 1644, thanks to Adam Wybe, whose horse-powered iron cableway was used in Gdańsk for constructing defensive structures.

Interestingly, cable-suspended transport was not originally a tourist attraction. Its main advantage has always been its ability to operate in areas with difficult terrain, an area where string transport can now also be applied.

Cable transport saw widespread use in the United States and the United Kingdom. By 1980, North America had over 500 miles of cable routes, transporting more than a million passengers annually. However, by the early 20th century, cable public transport began appearing in other regions, such as Europe, Central Asia, North Africa, New Zealand, China, and Russia, demonstrating steady growth.

Most recognized types of cable-suspended transport:

• Aerial tramway
• Gravity lift (rail-based)
• Cable railway
• Funicular
• Chairlift (cableway)
• Ski lift
• Surface lift
• Gondola lift
• Cargo cable conveyor
• Cable ferry
• Zip line (for climbers)
• Elevator

Modern Cable Transport Technologies

For many decades, cable-suspended transport remained a niche solution, used in specific locations for specific needs, especially where cars couldn’t reach. However, the changing social climate, driven by environmental concerns in megacities, is prompting municipal authorities to consider alternative modes of transport, including cable systems, with their pros and cons.

Today’s suspended transport includes gondola and aerial tramway lifts. Gondola lifts feature enclosed cabins attached to the cable via detachable clamps, with cabin stops managed by suspended conveyors. Aerial tramways also use enclosed cabins but move along powerful, enclosed support cables in a reversible motion between lower and upper stations. Both gondola and aerial tramway lifts are versatile forms of suspended transport. They are used not only to overcome geographical obstacles (steep slopes, rivers, dense forests, etc.) but also as urban transit solutions. These lifts exemplify continuous cable systems, equipped with looped traction ropes that rotate constantly between endpoints—drum shafts with electric drives—and between stations.

In large open areas, two-cable (aerial tramway) and three-cable (gondola) lifts are used. These systems include steel wheels that allow movement back and forth rather than in a loop. This rail-based cable transport offers high lateral stability and can operate effectively even in strong crosswinds. The beams of suspended transport, spaced at specific intervals, play a crucial role in this stability.

Unlike outdated operator-controlled systems, modern cable transport is fully or partially automated. These systems can move independently, slow down for easier boarding and disembarking, maintain comfortable cabin temperatures, and optimize lighting levels. uST transport and infrastructure complexes operate on similar principles.

What Is String Transport?

uST transport and infrastructure complexes carry passengers or cargo along string rail highways using rail-based unmanned vehicles (uPods). The uST system includes an automated control system, a string rail overpass composed of the track structure, intermediate supports and anchoring structures, and rolling stock. Typically, anchoring structures are integrated with passenger stations or other infrastructure facilities such as loading terminals, service centers, track switches, power supply units, and dispatch centers.

The track structure, or string rail, is an uncut steel or composite beam containing a bundle of pre-tensioned steel rods embedded in a special filler. This design ensures high strength and smoothness of the track. Depending on the maximum payload (ranging from 20 to 300 tons) and speed mode (from 100 to 500 km/h), the uST track structure can be rigid, semi-rigid, flexible, or semi-flexible.

The string rail used by uPods is exceptionally strong. Thanks to pre-tensioning technology, all horizontal loads are transferred to anchoring structures, while vertical loads are borne by intermediate supports. Anchoring structures are made of monolithic concrete, and intermediate ones consist of steel tubes with guy wires. The attachment of the supporting saddle to the track structure increases its load-bearing capacity eightfold.

Power for string rail complexes is provided via traction electricity through a contact rail. In the event of a power outage, each uPod can continue moving using its onboard battery, which has enough capacity to cover up to 28 km.

Advantages, Disadvantages, and Challenges

The indisputable advantages of cable (suspended) transport include:

• High environmental friendliness and zero CO₂ emissions
• Low noise pollution
• Simpler and more cost-effective construction compared to other infrastructure
• Low maintenance costs
• Low energy consumption
• Minimal land use during construction
• Fast construction speed
• Aesthetic appeal
• High integration into urban environments and natural landscapes
• Connectivity to remote and isolated locations
• Alternative to traditional transport
• High safety level
• Tourist appeal
   

Notable disadvantages of cable (suspended) transport:

• Vulnerability to weather conditions, especially lightning
• Relatively low travel speed (10–20 km/h)
• Limited passenger capacity and need for flow regulation
• Requirement to build supporting towers and beams for long routes
• Demanding maintenance frequency and quality
• Need for constant passenger safety monitoring

Comparative advantages of string transport (uST technology):

• Higher passenger throughput: uST technology can transport up to 50,000 passengers per hour in both directions, provided there are enough uPods on the line.
• Strong integration with other transport systems: uST stations can receive passengers directly from ground level, though most use elevated platforms (7.5 meters high), which can be integrated with metro lines, surface transport stations, and even shopping centers.
• Operational flexibility: Passenger flow can be dynamically adjusted throughout the day based on traffic density. The string rail overpass supports loads up to 60 tons.
• Shortest possible route: Terrain is irrelevant for uST, as the track follows the shortest trajectory. The structure can include vertical and horizontal curvature if needed.
• Environmental efficiency: For example, building a semi-rigid uST track requires only 0.1 hectares of land. The system runs on electricity and produces no harmful emissions.
• Automation, comfort, and safety: uST electric vehicles are equipped with advanced passenger safety systems. All operations are fully automated, though monitored by control operators. uPods feature multimedia modules, Wi-Fi, and climate control systems.

Since cableways are built above ground level, they are often mistakenly classified as aerial public transport. However, this is incorrect. True examples of aerial transport include airplanes, helicopters, and airships. Cable transport is traditionally referred to as an aerial tramway or cable cabin, and less commonly as a funicular.

So, what type of transport is a cableway? Technically, these systems fall under off-street passenger and cargo transport, equipped with steel cables. This track design allows key landscape points to be connected via the shortest route. In many cases, the slope of the terrain can reach 45°, which is impossible for other types of transport to overcome without additional infrastructure.

Global Implementation

Today, cableways are increasingly becoming intelligent transport systems. Among existing suspended transport routes, the most impressive examples are those that showcase the global integration of cableways into urban infrastructure. The most notable is the 16-kilometer Metrocable network of suspended railways, which has significantly transformed the economic capital of Colombia—Medellín. In 2004, municipal authorities began a radical overhaul of their logistics systems by connecting the cableway network to the metro for the first time, thereby introducing hybrid transportation solutions.

Authorities in Bolivia’s largest cities, La Paz and El Alto, faced a collapse of the limited road infrastructure between them, as traffic volumes far exceeded the capacity of ground routes. As an alternative, the company Mi Teleférico designed a comprehensive cableway system that has become one of the longest in the world. Currently, it consists of 11 lines and 36 stations, with a total route length of 33.8 kilometers. Mi Teleférico is unique in that it serves as the core of the urban transport network, rather than a supplementary system.

Another vivid example of a hybrid transport solution is the Roosevelt Island Tramway, a cableway crossing New York’s East River and connecting Roosevelt Island with Manhattan’s Upper East Side. Manufactured by Von Roll, these aerial trams can carry up to 110 passengers at a time and cover a distance of 960 meters. It is estimated that more than 2 million passengers use the Roosevelt Island Tramway annually.

The newest but equally important project is the Rakavlit cableway in Haifa, Israel, which was launched in 2022. It spans 4.4 kilometers and includes 148 cabin cars, each with a capacity of 10 passengers. Thanks to this route, passengers can easily reach key city destinations such as the HaMifratz Central Bus Station, the Technion, and the University of Haifa. This system transports up to 330,000 people per month.

Opportunities and Prospects

As previously mentioned, cable cars are increasingly seen as infrastructure of the future—a prime example of hybrid transportation solutions. Many leading manufacturers of suspended transport systems have formed large alliances to compete more effectively in the global market.

An unconventional approach to developing suspended systems is demonstrated by the international company Unitsky String Technologies Inc. from Belarus. Unlike traditional passenger rail transport, the concept of using string rail complexes fundamentally transforms the perception of public cable passenger transport and sets a new trajectory for its potential applications. To test all technologies, the first commercial uST project was implemented in Maryina Gorka. Additionally, UST Inc. is negotiating the deployment of string rail complexes in India, Nepal, the UAE, and Taiwan.

The Future of Cable Transport

As noted earlier, cable transport has evolved beyond being a tourist attraction or entertainment tool. Today, cable cars represent a mode of transport with significant potential. Given the current rate of urbanisation, these systems continue to play a growing role, albeit locally, and demonstrate sustainable development. Given the quality and rapid scaling of modern artificial intelligence technologies, cable car operations could become fully autonomous in the near future.

It’s likely that the very approach to designing suspended transport will shift: the somewhat outdated cable-based model may be replaced by more advanced string technologies, significantly increasing travel speed and, consequently, passenger throughput. A high degree of passenger mobility will enable the sale of mobility as a service, allowing hybrid transport solutions, combining underground, ground-level, and elevated routes, to form the infrastructure of the future.

It’s important to note that the more modern uST technology already offers several advantages over its venerable counterpart. First, unlike cable cars, string transport does not use bulky fuel-powered engines, which are noisy and less efficient than electric alternatives. Second, each unmanned vehicle on string rail highways can move autonomously, without being tethered to another, as is the case with reversible cable cars. Third, uST transport and infrastructure complexes are more technologically advanced and already equipped with automated control systems, making them more efficient.

Even in established urban areas with historic architecture, and in places where eco-friendly transport remains a trend, the introduction of above-ground transport can enhance tourist appeal and provide alternative connectivity for residents. In the future, such demands will remain relevant as populations in major cities continue to grow, along with stricter environmental regulations on harmful CO₂ emissions.

Conclusion

Despite challenging terrain and dense urban development, cable cars are among the key alternative solutions for cargo and passenger transportation. The cost of such projects depends directly on their complexity, route length, number of beams and supports, and weather conditions. Nevertheless, they remain more affordable than traditional asphalt or railway construction.

Moreover, cable cars and uST string rail highways can make cities or natural sites more attractive due to their low carbon footprint and minimal environmental impact. They ensure safety and mobility by following the shortest trajectory and serve as an effective tourism tool that boosts the popularity of key routes.