Bridges

Basic bridges

Bridges come in many forms. A very basic type merely consists of a plank or a stone slab, spanning a narrow stream, whereas slightly longer bridges are made from rope, branches, tree trunks, or beams.

These men in the Alborz Mountains, northern Iran, are crossing a river on a simple wooden bridge, constructed of tree trunks and branches, which rest on stone cairns, placed at intervals in the river bed. (Photo copyright © by Kaj Halberg)

Crossing rivers in the Himalaya is not always a simple affair. On several occasions, I have made hair-raising crossings on simple ‘bridges’, which simply consisted of narrow tree trunks, planks, or stone slabs.

In 1982, I undertook a demanding hike in the Nanda Devi National Park, Uttarakhand, India, together with two friends, John Burke and Ajai Saxena. On several occasions on our way back, we crossed the Rishi Ganga River on tree trunks or logs.

This interesting hike is related in depth on the page Travel episodes – India 1982: Pleasures of Nanda Devi.

Halfway across these two rather thin logs, resting precariously on rocks on either side of the river, John has come to a stop, and our guide Gabar Singh is on his way out to assist him. (Photo copyright © by Kaj Halberg)

During a hike in the Great Himalayan National Park, Himachal Pradesh, India, together with Ajai Saxena and his wife Madhu, the trail along the Tirthan River had been washed away by heavy monsoon showers, and a new ‘path’ had been constructed, much of it leading through the river itself.

This hike is described in depth on the page Plants – Plant hunting in the Himalaya: Abode of the deodar.

Assisted by our guide, Madhu Saxena crosses a ‘bridge’, which merely consists of tree trunks, onto which boards have been nailed. However, it was rather civilized compared to others that we crossed further upstream, which were thin logs, resting precariously on rocks. (Photo copyright © by Kaj Halberg)

During a hike in the Upper Langtang Valley, central Nepal, one of my porters is crossing a tiny stream on a simple bridge, consisting of stone slabs, resting on tree trunks. (Photo copyright © by Kaj Halberg)

In this picture, a tourist is balancing across rather thin logs, leading across the Langmoché Khola River, Langtang National Park. Following heavy monsoon rain, the original bridge had been washed away, but in less than half an hour, our porters had constructed this provisional ‘bridge’. (Photo copyright © by Kaj Halberg)

More advanced wooden bridges

The town of Nyaung Shwe, near Lake Inle, Myanmar, is criss-crossed by countless canals, spanned by a large number of wooden bridges. The following 5 pictures are from this town.

Stone bridges

In former days, many bridges were constructed from stones or bricks. Luckily, many of these fine old bridges have been preserved.

In Acadia National Park, Maine, United States, a total of c. 91 km of so-called carriage roads, besides a number of stone bridges, were constructed between 1913 and 1940. Motorized vehicles are banned on these roads, for the benefit of hikers, bikers, horseback riders, and carriages. They were financed by millionaire and philanthropist John D. Rockefeller, Jr. (1874-1960).

The bridge in the pictures below leads to the Solidor Tower (in fact three linked towers), located in the estuary of the river Rance, at the town of St. Servan, near Saint Malo, Brittany. It was built 1369-1382 by order of John V, Duke of Brittany, to control access to the river at a time, when the city of St. Malo did not recognize his authority. Later, the tower became a jail, and today it is a museum.

Old stone bridge, Bonneval-sur-Arc, Val d’Arc, France. Rosebay willow-herb (Chamaenerion angustifolium), alpine dock (Rumex alpinus) and other plants grow in cracks on the bridge. (Photos copyright © by Kaj Halberg)

This ruined bridge in north-western Iran, made of bricks, has collapsed. The lower picture shows a kestrel (Falco tinnunculus), which has made its nest in a cavity on the bridge. (Photos copyright © by Kaj Halberg)

Old stone bridge, spanning the Ljungan River, Jämtland, Sweden. In 1974, when this picture was taken, horse-drawn wagons were still a part of the traffic picture in Sweden. (Photo copyright © by Kaj Halberg)

The Blue Nile originates in Lake Tana in the Ethiopian Highlands, from where it makes its way c. 1,500 km to Khartoum, in the Sudan, where it joins the larger White Nile. The name Blue Nile is in fact a misnomer. During the summer monsoon, this river washes down huge amounts of soil from the highlands, which turns its water almost black. In a local Sudanese language, the word for black is also used for blue, so, in reality, the river should be called ‘The Black Nile’.

The first written account of the Blue Nile is from 1565, when a Portuguese, João Bermudes, who called himself Patriarch of Ethiopia, provided a description of the Blue Nile Falls, Tississat, in his memoirs.

Incidentally, to many Christian Ethiopians, the Blue Nile is identified as the sacred river Gihon, one of the four rivers flowing out from the Garden of Eden, as related in Genesis, 2:13.

Iron and steel bridges

The Long Bien Bridge is a so-called truss bridge, spanning the Red River in Hanoi, Vietnam, in Vietnamese called Hong Ha (‘Red Sunshine’) or Song Cai (‘Mother River’). A truss is an assembly of beams, steel bars, or steel-enforced concrete blocks, which are connected to make a solid structure, often forming a pattern of numerous triangles. The steel truss bridge was a major engineering breakthrough, as it can span distances of over 460 m. (Source: en.wikipedia.org/wiki/Cantilever_bridge)

The Long Bien Bridge was constructed by the French in 1899-1902, using more than 3,000 Vietnamese workers. At that time, with a length of 2.4 km, it was one of the longest bridges in Asia. Cars are not allowed on this bridge, which is reserved for trains, scooters, and motorcycles.

Before the independence of North Vietnam in 1954, this bridge was called the Paul Doumer Bridge, named for Paul Doumer (1857-1932), the Governor-General of French Indochina 1897-1902, and later French president 1931-1932.

The Chuong Duong Bridge is another truss bridge, spanning the Hong Ha River in Hanoi. It is 1.2 km long and has two lanes in each direction, reserved for cars, which have no access to the Long Bien Bridge.

The Makatote Viaduct near Ohakune, North Island, New Zealand, is a steel truss railway bridge, 262 m long, which spans the Makatote River, 79 m above the water. When this bridge was constructed in 1905-1908, it was the tallest viaduct in New Zealand. Today, the Mohaka and North Rangitikei viaducts are taller, at 95 and 81 m, respectively.

Cantilever bridges

This rather elaborate type of bridge has two so-called cantilevers, a structure consisting of beams, steel bars, or steel-enforced concrete blocks, which project horizontally or slightly upwards into the air from each shore. The cantilever is secured on the shore by a pile of heavy stones or a concrete block.

In shorter bridges, the two cantilevers are then connected by tying beams or bamboo poles across the gap, whereas larger cantilever bridges, designed for heavy traffic, are made from trusses (see Iron and steel bridges above).

This simple cantilever bridge, spanning the Tamur River, eastern Nepal, is constructed from long bamboo poles, secured at both ends in a heap of boulders, and supported by simple wooden structures. (Photo copyright © by Kaj Halberg)

During the Himalayan monsoon, torrential rain showers often cause landslides, which occasionally wash away houses, trails and bridges, forcing people to build simple temporary bridges, until new, stronger bridges can be constructed.

In autumn 1978, a huge tidal wave washed away a few villages and several bridges along the Dudh Kosi River, Khumbu, eastern Nepal. The following two pictures show a simple cantilever bridge, constructed shortly after the disaster.

In areas of the Himalaya, in which the Tibetan Buddhism, or Lamaism, is the dominant religion, bridges are often adorned with Buddhist prayer flags. These flags, and other aspects of Buddhism, are described in detail on the page Religion: Buddhism.

Simple cantilever bridge, near the village of Shyabru, Langtang National Park, Nepal. In the background numerous Buddhist prayer flags and a water-driven prayer wheel. The mantras written on the wheel are dispersed into the universe by the turning of the wheel, whereas the wind disperses the mantras printed on the prayer flags. (Photo copyright © by Kaj Halberg)

This porter, whose burden is protected from rain by a bright blue plastic sheet, is crossing a cantilever bridge, spanning a tributary to the Ghunsa River, eastern Nepal. Numerous strings, adorned with Buddhist prayer flags, have been strung across the river. (Photo copyright © by Kaj Halberg)

Suspension bridges

As its name implies, this bridge type is supported by suspension cables, attached either to structures on both sides of a river, as seen in many mountain areas, or, as is the case with longer bridges, to tall concrete towers.

In former times, suspension bridges in many mountain areas around the world were constructed from bamboo poles or branches, which were tied together and supported by twine ‘cables’ made from liana bark that were tied to a large tree on either side of the river. After some years of wear and tear, these rather flimsy structures would finally break, often causing casualties among men and beasts. Today, most suspension bridges in the mountains are solid steel structures, secured with strong steel cables, built into concrete blocks at both ends.

This suspension bridge, adorned with numerous Buddhist prayer flags, spans the Dudh Kosi River, near the confluence of this river and the Bhote Kosi River, Khumbu, eastern Nepal. (Photos copyright © by Kaj Halberg)

A large flock of goats and sheep cross a suspension bridge in the Lower Marsyangdi Valley, central Nepal. Both are described on the page Animals: Animals as servants of Man. (Photos copyright © by Kaj Halberg)

Heavily laden with planks, mules cross a steel suspension bridge, spanning the Kali Gandaki River, Mustang District, central Nepal. This cross between horse and donkey is described on the page Animals: Animals as servants of Man. (Photo copyright © by Kaj Halberg)

Golden Gate Bridge, San Francisco, California, is a suspension bridge, 2,737 m long, spanning the Golden Gate, the strait connecting San Francisco Bay with the Pacific Ocean. This bridge was opened in 1937, and, until 1964, it had the longest main span of any suspension bridge in the world, at 1,280 m. (Photos copyright © by Kaj Halberg)

In 2004, when I visited the Bhote Kosi Valley, central Nepal, this area was controlled by Maoist rebels, fighting against the government. I had to pay a ‘donation’ of 1000 Rupees, or I would not be allowed to pass this village, but otherwise the Maoists were very polite towards me.

In the picture below, my guide Ganga Thapa is standing next to a suspension bridge across the Bhote Kosi River, near the village of Jagat. The red banner on the bridge reads as follows: “Let us fight against the government. Help the low castes and get rid of the caste system.”

Brooklyn Bridge, New York City, spans the East River, forming the border between Brooklyn, Long Island, and the island of Manhattan. This famous bridge, which is 1,825 m long, with a main span of 486 m, was the first steel-wire suspension bridge to be constructed. Work was initiated in 1869, the construction lasting no less than 14 years.

This picture from 1998 shows the bridge, and Manhattan, at night. The twin towers of the World Trade Center, which were destroyed by terrorists on September 11, 2001, are seen in the background. (Photo copyright © by Kaj Halberg)

Covered wooden bridges

In former days, the eastern half of North America held more than 13,000 covered wooden bridges, most of which were constructed in the 1800s. The covering was intended as a means to prolong the life-span of the bridge, which, without covering, would deteriorate after only 10 to 15 years.

Many of the covered bridges are truss bridges, and in a special type, called lattice bridges, a large number of small planks are placed diagonally to form a lattice.

About 1,500 covered bridges have been preserved in the United States, four of which are shown below.

Hart Bridge is another lattice bridge, built c. 1864, 52 m long and 4.6 m broad, which spans the Housatonic River, West Cornwall, Connecticut. It was constructed of timber from red spruce (Picea rubens), using wooden pegs, or trunnels, to join the timbers. Blooming yellow iris (Iris pseudacorus) is seen in the foreground. (Photos copyright © by Kaj Halberg)

Smith Bridge, near Plymouth, New Hampshire, is a truss bridge, 45.5 m long. It was constructed in 1850. The arches are a later addition. Here it is photographed in rainy weather. (Photo copyright © by Kaj Halberg)

Europe also holds a few covered wooden bridges.

Concrete bridges

Most modern bridges are constructed of concrete, reinforced with steel bars.

This bridge near the Cing Yun Waterfall, south of Alishan, Taiwan, has been adorned with a Buddha statue and a stylized pattern, depicting a sharp-nosed pit viper (Deinagkistrodon acutus), the totem animal of several Taiwanese indigenous peoples. (Photo copyright © by Kaj Halberg)

Highway, Les Grangettes, Geneva Lake, Switzerland. The tree in the foreground is a night roost of great cormorants (Phalacrocorax carbo), whose white dung has covered it completely. (Photo copyright © by Kaj Halberg)

The Terenez Bridge, located between Landévennec and Rosnoën, Crozon Peninsula, Brittany. It is 515 m long, with 2 pylons, from which cables support the curved bridge deck. (Photos copyright © by Kaj Halberg)

These cows, chewing their cud on a bridge across the Parvati River, Himachal Pradesh, India, are blocking part of the traffic. Judging from the large piles of dung on the bridge, it constitutes a favourite resting place for these cows. – Cattle are described on the page Animals: Animals as servants of Man. (Photo copyright © by Kaj Halberg)

In the city of Trondheim, Norway, Gamle Bybro (‘Old Town Bridge’) crosses the Nidelva River from the main street Kjøpmannsgata to the neighborhood of Bakklandet. This bridge was constructed in 1681. The buildings in the background are former warehouses for wealthy traders. (Photo copyright © by Kaj Halberg)

Rainbow Bridge spans the Neches River in south-eastern Texas, connecting the cities of Port Arthur and Bridge City. The latter was originally named Prairie View, as it was located on coastal grasslands. In 1938, when the Rainbow Bridge was constructed, the name was changed to Bridge City, as you now had to cross a bridge to enter the city, regardless of the direction you came from. (Photo copyright © by Kaj Halberg)

Victoria Falls Bridge spans the Zambezi River near Victoria Falls. This river constitutes the border between Zimbabwe and Zambia.

Modern bridges, reserved for pedestrians and cyclists

Droichead na Leathphingine, in English called Halfpenny Bridge (often shortened to Ha’penny Bridge), is a pedestrian iron bridge, spanning the Liffey River in Dublin, Ireland. It was constructed in 1816. (Photo copyright © by Kaj Halberg)

Te Rewa Rewa Bridge is a futuristic suspension bridge, spanning the small Waiwhakaiho River in New Plymouth, New Zealand. This bridge, which was completed in 2010, is reserved for pedestrians and cyclists. (Photos copyright © by Kaj Halberg)

Concrete foot bridge with wooden rails, Hanoi, Vietnam. It can hardly be called ‘bridge over troubled water’, but perhaps the stream holds water after a heavy shower. (Photo copyright © by Kaj Halberg)

When small, the weeping fig (Ficus benjamina) is a very popular house plant, but in the wild it grows enormous, sprouting numerous aerial roots from its branches, which grow down to the ground, where they take root, over the years becoming additional trunks, creating an entire patch of ‘forest’, which is in reality a single tree. This species is native to the Indian Subcontinent, east to southern China and Taiwan, and thence southwards through Southeast Asia and Indonesia to northern Australia, and eastwards to the Pacific.

The weeping fig, as well as other fig tree species, are described in depth on the page Plants: Fig trees.

(Uploaded September 2017)

(Latest update August 2024)

Kaj Halberg - writer & photographer

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Bridges