<P> The following timeline covers European exploration from 1418 to 1957 . </P> <P> The 15th century witnessed the rounding of the feared Cape Bojador and Portuguese exploration of the west coast of Africa, while in the last decade of the century the Spanish sent expeditions to the New World, focusing on exploring the Caribbean Sea, and the Portuguese discovered the sea route to India . In the 16th century, various countries sent exploring parties into the interior of the Americas, as well as to their respective west and east coasts north to California and Labrador and south to Chile and Tierra del Fuego . In the 17th century, the Russians explored and conquered Siberia in search of sables, while the Dutch roughly worked on the chart for Australia . The 18th century saw the first extensive exploration of the South Pacific and the discovery of Alaska, while the nineteenth was dominated by exploration of the polar regions (not to mention excursions into the heart of Africa). By the 20th century, the poles themselves had been reached . </P> <Ul> <Li> 1418--João Gonçalves Zarco and Tristão Vaz Teixeira discover Porto Santo . </Li> <Li> 1419--Gonçalves and Vaz discover Madeira . </Li> <Li> 1427--Diogo de Silves discovers the Azores . </Li> <Li> 1434--Gil Eanes passes Cabo de Não and rounds Cape Bojador . </Li> <Li> 1443--Nuno Tristão passes Cape Blanco . </Li> <Li> 1444--Dinis Dias reaches the mouth of the Senegal River . </Li> <Li> 1446--The Portuguese reach Cape Verde and the Gambia River . </Li> <Li> 1456--Alvise Cadamosto and Diogo Gomes explored the Cape Verde Islands . </Li> <Li> 1460--Pêro de Sintra reaches Sierra Leone . </Li> <Li> 1470--Cape Palmas is passed . </Li> <Li> 1472--Fernão do Pó discovers Bioko . </Li> <Li> 1473--Lopo Gonçalves is the first to cross the equator . </Li> <Li> 1474--75--Ruy de Sequeira discovers São Tomé and Príncipe . </Li> <Li> 1482--Diogo Cão reaches the Congo River, where he erects a "padrão" (pillar of stone). </Li> <Li> 1485--86--Cão reaches Cape Cross, where he erects his last padrão . </Li> <Li> 1487--92--Pêro da Covilhã travels to Arabia, down to the mouth of the Red Sea, eastward by sail to the Malabar Coast (visiting Calicut and Goa); later sails down the east coast of Africa (visiting the trading stations of Mombasa, Zanzibar, and Sofala); on his return he visits Mecca and Medina before reaching Ethiopia in search of the mythical Prester John . </Li> <Li> 1488--Bartolomeu Dias rounds the "Cape of Storms" (Cape of Good Hope). </Li> <Li> 1492--Christopher Columbus discovers the Bahamas, Cuba, and "Española" (Hispaniola). </Li> <Li> 1493--94--Columbus discovers Dominica and Guadeloupe, among other islands of the Lesser Antilles; also discovers Puerto Rico and Jamaica . </Li> <Li> 1497--John Cabot discovers Newfoundland . </Li> <Li> 1497--98--Vasco da Gama sails to India and back . </Li> <Li> 1498--Columbus discovers the mainland of South America . </Li> <Li> 1499--Alonso de Ojeda explores the South American mainland from about Cayenne (in modern French Guiana) to Cabo de la Vela (in modern Colombia), discovering the mouths of the Orinoco and entering Lake Maracaibo . </Li> <Li> 1499--Amerigo Vespucci discovers the mouth of the Amazon River and reaches 6 ° S, in present - day northern Brazil . </Li> <Li> 1499--João Fernandes Lavrador, together with Pêro de Barcelos, sight Labrador . </Li> <Li> 1499--Gaspar and Miguel Corte - Real reach and map Greenland . </Li> </Ul> <Li> 1418--João Gonçalves Zarco and Tristão Vaz Teixeira discover Porto Santo . </Li>

What events led to the discovery of america
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