Circumnavigation – literally, "navigation of a circumference" – refers to travelling all the way around an island, a continent, or the entire planet Earth.

In principle, if a person walks completely around either Pole, they will have crossed all meridians, but this is not generally considered a "circumnavigation." A basic definition of a global circumnavigation would be a route which covers at least a great circle, and in particular one which passes through at least one pair of points antipodal to each other. In practice, different definitions of world circumnavigation are used, in order to accommodate practical constraints depending on the method of travel. Since the planet is a sphere, a trip from one Pole to the other, and back again, would technically be a circumnavigation, but practical difficulties generally preclude such a voyage.

For the wealthy, long voyages around the world, such as was done by Ulysses S. Grant, became possible in the 19th century, and the World Wars moved vast numbers of troops around the planet. However, it was later improvements in technology and rising incomes that made such trips relatively common.

Laura Dekker (born 20 September 1995) is a Dutch sailor. In 2009, she announced her plan to become the youngest person to circumnavigate the globe single-handed. A Dutch court stepped in, due to the objections of the local authorities, and prevented Dekker from departing while under shared custody of both her parents. In July 2010, a Dutch family court ended this custody arrangement, and the record breaking attempt finally began on 21 August 2010. Dekker successfully completed the solo circumnavigation in an 11.5-metre (38 ft) two-masted ketch, arriving in Simpson Bay,Sint Maarten, on 21 January 2012.

Dekker was born on a boat in the port of Whangarei, New Zealand during a seven-year trip by her parents. Her father, Dick Dekker, is Dutch and her mother, Babs Müller, is German; thus, Dekker has Dutch, German, and New Zealand citizenship. Her parents divorced in 2002.

Dekker spent the first four years of her life at sea. At six, Dekker owned her first boat, an Optimist, and learned to sail it herself. The next boat she received at the age of ten was a Hurley 700. She named it Guppy and used it for solo-sailing during her multiweek-long summer vacations; her trips included the Wadden Sea and the North Sea. In May 2009, Dekker made a solo-crossing from Maurik, Netherlands to Lowestoft, England where local authorities requested her father to come and accompany her on her return voyage.

Ferdinand Magellan (Portuguese: Fernão de Magalhães, IPA: [fɨɾˈnɐ̃w ðɨ mɐɣɐˈʎɐ̃jʃ]; Spanish: Fernando de Magallanes, IPA: [ferˈnando ðe maɣaˈʎanes]; c. 1480 – 27 April 1521) was a Portuguese explorer. He was born in Sabrosa, in northern Portugal, and served King Charles I of Spain in search of a westward route to the "Spice Islands" (modern Maluku Islands in Indonesia).

Magellan's expedition of 1519–1522 became the first expedition to sail from the Atlantic Ocean into the Pacific Ocean (then named "peaceful sea" by Magellan; the passage being made via the Strait of Magellan), and the first to cross the Pacific. It also completed the first circumnavigation of the Earth, although Magellan himself did not complete the entire voyage, being killed during the Battle of Mactan in the Philippines. (For background see Exploration of the Pacific).

Magellan also gives his name to the Magellanic Penguin, which he was the first European to note, and the Magellanic clouds, now known to be nearby dwarf galaxies.