A zip-line (or zip line, zipline, Sypline, zip wire, aerial runway, aerial ropeslide, death slide, flying fox, or, in South Africa, foefie slide) consists of a pulley suspended on a cable, usually made of stainless steel, mounted on a slope. It is designed to enable a user propelled by gravity to travel from the top to the bottom of the inclined cable by holding on to, or attaching to, the freely moving pulley. Zip-lines come in many forms, most often used as a means of entertainment. They may be short and low, intended for child’s play and found on some playgrounds. Longer and higher rides are often used as a means of accessing remote areas, such as a rainforest canopy. Zip line tours are becoming popular vacation activities, which are found at outdoor adventure camps or upscale resorts, where they may be an element on a larger challenge or ropes course. The jungles of Costa Rica, Florida, Puerto Vallarta, and Nicaragua are popular destinations for zip line enthusiasts.

History
The zip-wire has been used as a transportation method in some mountainous countries for many years. In some remote areas in China such as Nujiang (Salween) valley in Yunnan, zip lines served the purposes of bridges across rivers, but due to a poor safety record, they have mostly been replaced by real bridges by 2015. Referred to as “an inclined strong”, one appears in The Invisible Man by H. G. Wells, published in 1897, as part of a Whit-Monday fair.

In 1739, Robert Cadman, a steeplejack and ropeslider, died when descending from Shrewsbury’s St Mary’s Church when his rope snapped.

Alberto Santos-Dumont used a direct ancestor of the zip-line in spring 1906 for a method of testing various characteristics of his Santos-Dumont 14-bis pioneer era canard biplane, before it ever flew under its own power later that year.

In the Australian outback, zip-lines were occasionally used for delivering food, cigarettes or tools to people working on the other side of an obstacle such as a gully or river. Australian troops have used them to deliver food, mail and even ammunition to forward positions in several conflicts.

Application of the zip line
A zip line can be used as:

method of physical training, for example in the army (commando);
obstacle course activity in outdoor sports (caving, mountaineering,…);
leisure activity, such as Adventure Park, canopy tours (tour of the canopy), etc.
cheap means of transport for people or goods (equipment, animals, etc.) in poor and / or uneven regions where the construction of a bridge or a bridge is not an option;
means of escape for isolated victims in a high place or difficult to reach by conventional means of transport (in the mountains, underground, etc.).

Tyrolean Equipment

Basic zip line
The simplest equipment does not require any equipment other than the rope (rope, cable…). Its use is then reserved for the passage of people. The individual is lying on the rope (the face of the head against the rope or cable). He restrains himself with one leg bent on this rope. The other leg is hanging. The progression is done by the strength of the arms. This method is long, painful and dangerous. It is confined to short crossings and / or purely sporting exercises.

Zipline arranged
The zip line can also include a pulley that slides along the rope and thus facilitates the progression. Utility at first, this technique is now adopted as an attraction in the leisure parks as part of an adventure trail in the forest.

Installation of the zip line
There are several variants of zipline installation, depending on the number of ropes, the type of mooring at the ends and the nature of the moving equipment.

In particular, the mooring of the ropes at the ends can be either fixed or adjustable by counterweight.

The pre-positioning of the rope can be done manually and statically, by unrolling the rope to the ground before putting it in tension. This method is suitable only for short ziplines and whose course does not cross any significant obstacles to the progression.

When such an installation is not possible, dynamic methods should be used. For example:

the launch of a flexible rope of small diameter and reduced weight (cord) which will then pull the final rope;
helicopter carriage of the final rope.

Professional courses
Professional versions of a zip-line are most typically used as an outdoor adventure activity. In contrast to “flying foxes” professional courses are usually operated at higher speeds, covering much longer distances and sometimes at considerable heights. The users are physically attached to the cable by a harness that attaches to a removable trolley. A helmet is required on almost all courses of any size.

Cables can be very high, starting at a height of over 9 m (30 ft), and traveling well over 460 m (1,510 ft). All zip-line cables have some degree of sag. The proper tensioning of a cable is important and allows the ability to tune the ride of a zip line.

Zip lines are a common way to return participants to the ground at the end of a ropes adventure course.

Braking
Users of zip-lines must have means of stopping themselves. Typical mechanisms include:

Friction created between the pulley against the cable.
Thick, purpose-built leather gloves.
A mat or netting at the lower end of the incline.
A passive arrester system composed of springs, pulleys, counterweights, bungee cord, tire or other devices, which slows and then stops the trolley’s motion.
A “capture block” which is a block on the cable that is tethered to a rope controlled by a staff who can manually apply friction on the rope to slow the user down.
Gravity stop, exploiting the sag in the cable. The belly of the cable is always lower than the termination point. The amount of uphill on a zip line controls the speed at which the user arrives at the termination point.
Hand brake at the end of the zip line.

Safety
With proper knowledge and training on the part of the operators, along with good maintenance, zip lines are generally safe and easy to use. In 2012 there were an estimated 200 commercial zip lines in the US and a further 13,000 private ones resulting in 3,600 visits to the emergency room.

Records
The world’s longest zip-line as of January 2018 is the 2.8 kilometer ‘Jebel Jais Flight’ at Jebel Jais in Ras Al Khaimah, United Arab Emirates.

“Parque de Aventura Barrancas del Cobre” at 2545 m (8,350 ft) in Copper Canyon, Mexico was once the longest.

In 2012, ZipFlyer Nepal (HighGround Adventures) was the world’s steepest with max incline of 56%, is currently second in the world and is still the tallest zip line. It had a vertical drop of 610 m (2,000 ft).

On 19 September 2015 the world’s steepest zipline was opened at Letalnica bratov Gorišek, on the ski flying hill in Planica, Slovenia. It is 566 metres (1,857 ft) long with a 202 metres (663 ft) vertical drop. It has an average 38.33% and a maximum 58.6% incline. The longest zipline in Europe, at just over 1600 meters long, is the Zip World Bethesda line in Penryn Quarry, Bethesda, Wales. The Zip World Bethesda line also holds the record for being the fastest Zip-Line in the world.

The longest zipline in England is the Skywire at the Eden Project in Cornwall measuring 660 meters (2,165 ft).

Zip-line trolley
The zip-line trolley is the frame or assembly together with the pulley(s) also known as sheave(s) inside that run along the cable. (The term “trolley” is more often used when this assembly consists of more than a single pulley with simple hanger and bearing.) Often more than one pulley is used to spread the load over more than one spot on the cable, to reduce cable bending stresses that may lead to metal fatigue and cable breakage. This also reduces any tendency of a pulley to twist sideways and run off the cable, with disastrous results. In addition, the trolley is usually shaped with guards to hold the cable in the groove(s) of the pulley(s).

A pivoting link, such as a carabiner, is used to secure the load to the trolley so that the trolley does not have a tendency to rock and thus fall off the cable if the load should sway. Load carriers ranging from enclosed cabins to gondolas to harnesses are attached to the link. Occasionally the load carrier is just a handhold or handlebar, although there is the danger of the rider losing his grip and falling. Such a simple carrier should be used only on zip lines that are near the ground or over water. The rider losing his grip due to the use of the simple carrier has led to a number of deaths.

Transportation
Yungas, Bolivia, features a system of zip lines used for transporting harvested crops.

Ziplining guide
Zip line courses can consist of one or many cables that are suspended between trees or man-made structures. Participants (often referred to as “zippers”) are suspended from a pulley that moves across the cable, propelled by gravity. The cables are mounted descending from a higher to lower point. The amount of incline as well as the weight of the zipper determines the speed at which the participant travels from point to point.

Zip line courses can be designed purely for speed (adrenaline rush), while others are designed to allow zippers to enjoy the natural surroundings such as forest, jungle or waterfalls (often referred to as canopy tours). Others employ elements of both.

Learn
Professional zip line courses offer mandatory training sessions for participants. During the training sessions guides teach participants, proper form, how to take off from a platform, how to land on a platform and how to break/slow down. Depending on the complexity and difficulty of the course, training sessions can take anywhere from a few minutes to a half-hour.

Do
Since courses are built to deliver varying experiences, it is a good idea to research courses to ensure you get the kind of experience that is most appealing to you. It is also important to keep in mind that courses have different age, health and weight requirements, so check with the tour provider before heading out for your adventure.

Buy
It is likely you will get all of the gear you need from the zip line operator including gloves, harnesses and helmets. However, many courses do require:

Closed-toe shoes
Since courses are almost always outdoors, be sure to wear weather-appropriate clothing.

Stay safe
Be sure you are provided with and wear a helmet, leather/suede gloves (if using your hand to break/slow down) and that the course has a good safety record. Professional US zip line courses often have double cables, ensuring that if one cable is compromised, a second will continue to carry the zipper. It is also important to adhere to all safety requirements given during the training session and to advise guides of any health issues.

With children
Courses have different age an weight requirements, so check with the course operator before heading out on your adventure.

Destinations
Zip Line courses include:

South Africa

Eastern Cape
Tsitsikamma Falls – over gorges across the Kruis River, near Storms River and the Tsitsikamma National Park
Tsitsikamma Forest – in the indigenous Tsitsikamma forest, over ancient yellowood trees, near Storms River and the Tsitsikamma National Park.

KwaZulu-Natal
Drakensburg – over indigenous forest in the Drakensberg Mountains.
Karkloof – over mist belt forest in the Karkloof Forest Reserve near Howick.

Limpopo
Magoebaskloof – over indigenous forest and ancient mountain cliffs overlooking the spectacular Groot Letaba River gorge, near Tzaneen.

Western Cape
Cape Canopy Tour – in the Hottentots Holland Mountains near Grabouw.

Swaziland
Malolotja – over the pristine mountain wilderness of the Malolotja Nature Reserve.

United States of America
Alaska
Alaska Zipline Adventure, toll-free
California
Sonoma Canopy Tours.
Colorado
Captain Zipline.
Hawaii
Kapalua Adventures.
Idaho
Tamarack Canopy Zipline Tour.
Georgia
Lake Lanier Canopy Tours.
North Carolina
ZipQuest Waterfall & Treetop Adventure.
Ohio
Hocking Peaks Adventure Park, St. Rt. 664 South, Logan, Ohio.
Pennsylvania
1 Refreshing Mountain Retreat and Adventure Center, 455 Camp Road, Stevens, PA
Texas
Lake Travis Zipline Adventures, 14529 Pocahontas Trail Leander, Texas 78641.

Australia
Queensland
Jungle Surfing Canopy Tours, 24 Camelot Close, Cape Tribulation, Queensland.
Tasmania
Hollybank Treetops Adventure, 66 Hollybank Road, Underwood, Tasmania.

United Kingdom
Scotland
Zip Trek Park, Alvie, near Aviemore. 14 zip wires over a 2km course.
Wales
Zip World Velocity, Penrhyn Slate Quarry, near Bethesda, North Wales. The longest zipline in Europe, over 1600m long.
Zip World Titan, Llechwedd Slate Caverns, Blaenau Ffestiniog, North Wales. Includes a four-person zipline.

Source from Wikipedia