320 BC Pytheas (Marseille) discovered “Thule”, possibly Iceland, Norway, or the Shetland Islands.
870 AD Floki Vilgerdarson (Norseman) discovered Iceland.
983 AD Eric the Red (Norseman) landed on western coast of Greenland and founds a colony.
1400 Nicolò and Antonio Zeno (Italy) possibly explored North Atlantic.
1497-98 John Cabot (Italy) explored North Atlantic.
1508-09 Sebastian Cabot (Italy) explored North Atlantic.
1553 Hugh Willoughby and Richard Chancellor (England) explored the White Sea and reached 72° N on the Novaya Zemlya coast.
1587 John Davis (England) reached 72.20 off Greenland.
1594-97 Willem Barentsz (the Netherlands) discovered Svalbard (Spitsbergen), rounded Novaya Zemlya and explored the Barents Sea.
1607-11 Henry Hudson (England) discovered Jan Mayen and the Hudson Strait, reached 80.38 N° off Svalbard.
1615 William Baffin (England) explored Baffin Bay, Baffin Island.
1648 Semyon Dezhnev (Russia) sailed around the Chukotka Peninsula from Kolyma to Anadyr.
1728 Vitus Bering (Russia) explored Bering Sea, Bering Strait.
1740-42 Vitus Bering and Aleksey Chirikov (Russia) reached Alaska from Kamchatka and discovered many of the Aleutian Islands and the Komandorsky Islands.
1773 Constantine Phipps (Britain) reached 80.80 N°.
1806 William Scoresby (Britain) reached 81.50 N° off Svalbard.
1819-20 William Parry (Britain) explored the Northwest Passage from the east to Melville Island.
1831 James Ross (Britain) attempted Northwest Passage from both east and west.
1845-47 John Franklin (Britain) and his entire expedition perished in the Canadian Arctic, seeking the Northwest Passage.
1869-70 Carl Koldewey (Germany) explored North East Greenland.
1872-74 Carl Weyprecht and Julius Payer (Austro-Hungarian) discovered Franz Josef Land.
1876 Albert Markham (Britain) reached 83.34 N° off Ellesmere Island.
1878-79 Nils Adolf Erik Nordenskjöld (Sweden) traversed the Northeast Passage.
1878-79 Giacomo Bove (Italy) joined the AE Nordenskjöld expedition.
1879-82 George De Long (USA) discovered the De Long Islands.
1881-84 Adolphus Greely (USA) leads ill-fated expedition to Ellesmere Island and west coast of Greenland.
1882-83 First International Polar Year.
1888 Fridtjof Nansen 
(Norway) crossed Greenland by ski from east to west (see biography).
1891-92 Robert Peary (USA) proved Greenland an island by crossing northeast corner.
1893-96 Fridtjof Nansen (Norway) drifted with the ship Fram towards the Pole and reached 86.22 N° (see biography).
1897 Salomon Andrée (Sweden) tried balloon flight over the North Pole but the party perished.
1899-1900 Luigi Amedeo d’Aosta Duca degli Abruzzi and Umberto Cagni (Italy) reached 86.57 N° off Franz Josef Land.
1903-06 Roald Amundsen (Norway) traversed the Northwest Passage in the Gjoa and fixed the approximate location of north magnetic pole (see biography).
1906-18 Vilhjalmur Stefansson (Canada) explores about 100,000 square miles in Canadian Arctic.
1908 Frederic Cook (USA) claimed he reached the North Pole.
1909 Robert Peary (USA) claimed he reached the North Pole.
1910-15 The Russian Arctic Ocean Hydrographic Expedition onboard icebreakers Vaygach and Taymyr charted the North East Passage and discovered Severnaya Zemlya Islands.
1918-20 Roald Amundsen (Norway) sailed the North East passage on board the Maud (see biography).
1925 Roald Amundsen (Norway) and Lincoln Ellsworth flew north from Svalbard in 2 aircraft and crashed 87.83 N°.
1926 Richard Byrd (USA) and Floyd Bennett claimed to have flew from Svalbard to the North Pole and back.
1926 Roald Amundsen (Norway), Lincoln Ellsworth and Umberto Nobile flew over the North Pole by airship Norge.
1928 George Hubert Wilkins (Australia) flew over the North Pole from Point Barrow to Svalbard.
1928 Umberto Nobile (Italy) flew over the North Pole by the dirigible Italia but on the way back to Svalbard crash landed in the pack ice.
1928 Gennaro Sora (Italy) and Sjef van Dongen discovered Alpiniøya and mapped Nordaustlandet.
1928-29 Gianni Albertini (Italy) explored and circumnavigate Nordaustlandet.
1930-31 Alfred Wegener (Germany) was part of several expeditions to Greenland.
1932-33 Second International Polar Year.
1934 Leonardo Bonzi
(Italy) mapped the south coast of Scoresby Sound.
1937 Valeri Chkalov and Mikhail Gromov (USSR) flew nonstop transpolar from Moscow to the United States.
1937 Ivan Papanin (USSR) landed by plane on ice floe near North Pole and with his party established the first Arctic drift station.
1937-40 Icebreaker Georgi Sedov (USSR) drifted to 86° 39″ N.
1954 U.S.S.R. Arctic Institute discovered the mountain range below surface of the Arctic Ocean.
1958 Nuclear-powered submarine Nautilus (USA) crossed the North Pole beneath the Arctic ice cap.
1959 Nuclear-powered submarine Skate (USA) surfaced at the North Pole.
1977 Nuclear-powered icebreaker Arktika (USSR) reached the North Pole by sea.
1986 Ann Bancroft (USA) is the first woman to travel to the North Pole on foot.
1991 Nuclear-powered icebreaker Sovetsky Soyuz (USSR) reached the North Pole by sea crossing the Arctic Ocean from Murmansk to Providenya.
2007-09 Third International Polar Year.