For most of us, lighthouses are synonymous with trips to the shore. But for seafarers, lighthouses have represented a vital symbol of safe passage for centuries. In fact, they go back to 280 BC, when the famed Lighthouse of Alexandria was built -- though lighthouses of the ancient world looked more like battlements than the candy-striped variety we know today.
The construction of lighthouses exploded during Age of Discovery, when nations sought out stakes in the New World. In the 18th century, with the invention of the Fresnel lens -- which made it possible to see lighthouse lights from many miles away -- the modern lighthouse was born. Today, with the advent of GPS, many of these beauties are more tourist attraction than lifeline to the shore -- but many of them are. Check out 23 highlights, below.
Top picture: Rattray head lighthouse on the north east coast of Scotland, by Grant Glendinning
Madang lighthouse, in Papua New Guinea, was built in 1959 as a memorial to the coast-watchers during World War II.
Picture: Kahunapule Michael Johnson
Cabo Branco Lighthouse in João Pessoa, Brazil, sits at the easternmost inland point of the Americas.
Enoshima lighthouse, Japan, was renovated in 2003 to include the snazzy lights and observation decks you see here.
Low Lighthouse, in Burnham-On-Sea, UK, is one of the smallest lighthouses in the world. It was built in 1832 and is still in use.
Picture: Michael Warren
Kiz Kulezi, in Istanbul, is also known as the Maiden Tower.
Picture: Ibrahim Usta/AP
Cape Hatteras lighthouse, the most recognised US coastal symbol, stands proudly on the Outer Banks of North Carolina -- despite being battered by numerous hurricanes. More than a million bricks were used to build it, and it's still the tallest lighthouse in America.
Picture: Ruth Fremson/AP
Sullivan's Island lighthouse is a more modern lighthouse -- it lights the way using a lamp capable of producing a massive 28,000,000 candlepower. Compared to other lighthouses, it's futuristic -- the facilities inside including air-conditioning and a lift.
Moncloa Lighthouse, aka Faro de la Moncloa, in Madrid, is a 330-foot-high transmission tower with an observation deck. It was designed by the architect Salvador Pérez Arroyo and built in 1992.
Picture: Miguel Palacios/Cover/Getty Images
The stark Knarrarós lighthouse was built in 1938 -- and remarkably, it is the tallest building in southern Iceland (at a towering 26m!).
Picture: Seli Oskarsson
Kanchanaphisek lighthouse, on Promthep Cape, Thailand. One of the world's newest lighthouses is this strange-looking, gold-topped specimen in Thailand. It was built in 1996 to honour the reign of king Bhumibol Adulyadej.
Picture: ADwarf/Wikimedia Commons
The Sand Island lighthouse has stood off Alabama's coast since the 1870s. The tower outlasted its namesake island, which washed away years ago. The 40m tall tower is abandoned, cracked and crumbling, but the state of Alabama can't afford to renovate.
Picture: Dave Martin/AP
Gorliz, Spain, Basque Country.
Middle Bay lighthouse is a hexagonal-shaped lighthouse offshore of Mobile, Alabama, in the centre of Mobile Bay. Built in 1885, the middle bay lighthouse is an example of a "screw pile" lighthouse, which are screwed into piles sitting on sea or river beds.
Stanislav Range Rear (Adzhiogol) Lighthouse is a vertical lattice hyperboloid structure, serving as an active lighthouse about 30km from Kherson, Ukraine. At a height of 64m, it is the tallest lighthouse in Ukraine.
Picture: Remembering Letters
Torre de Hércules, or the Tower of Hercules, is an ancient Roman lighthouse on a peninsula near A Coruña, Galicia, in north-western Spain. The lighthouse is almost 1900 years old -- it's the oldest Roman lighthouse in use today and one of the three oldest operational lighthouses in the world.
Picture: Alfonso Maseda
Lighthouse at the End of the World, Tierra del Fuego, Argentina. Les Eclaireurs Lighthouse (the French name "Les Éclaireurs" means "the Enlighteners" or "the Scouts") is a slightly conically shaped lighthouse standing on the Les Eclaireurs islets, in southern Argentina. Today probably the most photographed lighthouse in South America.
Picture: Mariana Silvia Eliano/Cover/Getty Images
Cape Otway lighthouse, first lit in 1848, is the oldest lighthouse in Australia. These days, you can rent out the space for vacation. Eight ships were wrecked along the coast of Cape Otway, including the first American vessel sunk during World War II.
Picture: Shiny Things
The historic Windward Point Lighthouse that is located within the grounds of the U.S. Naval Station at Guantanamo Bay, Cuba. Made of iron, built in 1903.
Picture: Mandel Ngan-Pool/Getty Images
The lighthouse of Blankenese, Hamburg, Germany. The remotely controlled, 45m tall, red and white striped concrete steel lantern house was built in 1984 and stands in the Elbe River.
Picture: Stuart Franklin/Getty Images
Huge waves crash against the South Gare lighthouse on March 24, 2013 in South Gare, Teesside, England. The lighthouse was built in 1884 and still operates using the original lenses.
Picture: Ian Forsyth/Getty Images
The stricken cruise ship Costa Concordia lies grounded a short distance beyond one of the two lighthouses on the coastline at Giglio Porto on January 19, 2012, on the island of Giglio in Italy.
Picture: Tullio M. Puglia/Getty Images
This lighthouse in Dungeness, Kent, England was built in 1961, in a desolate landscape of wooden houses, a nuclear power station and several lighthouses.
Picture: Dan Kitwood/Getty Images
The Lanterna, the ancient and famous lighthouse of Genoa, Italy. Genoa has the largest seaport in Italy, which makes its lighthouse incredibly important. It's 76m tall, which makes it the world's second tallest "traditional" lighthouse.
Picture: Vittorio Zunino Celotto/Getty Images
An aerial view of the South Solitary Lighthouse on South Solitary Island, in Australia. The now-uninhabited island is only open to the public for nine days in July. And besides a few nights during the Second World War, its light has never gone out.
Picture: Lisa Maree Williams/Getty Images
Kõpu lighthouse (Estonian: Kõpu tuletorn) is one of the best known symbols and tourist sights on the Estonian island of Hiiumaa. It is one of the three oldest still-operational lighthouses in the world, having been in continuous use since its completion in 1531!
An arctic lighthouse in Hraunhafnartangaviti, Iceland.
Arctowski lighthouse at Arctowski Station is the southernmost lighthouse of the world. The base established in 1977.
Picture: Acaro/Wikimedia Commons