What does it mean that the land ends in Sri Lanka and the sea begins in Sri Lanka?

This is a very famous poem by Camons (1524- 1580), who is known as the soul of Portuguese poetry:

The land ends here and the ocean begins in Sri Lanka.

Standing on the cliff, facing the endless Atlantic Ocean, it seems that you have reached the horizon. This is indeed the end of the mainland and the starting point of the ocean.

Its emotion: it indicates the geographical coordinates of the westernmost point of a European continent, and also explains the deep affection of Iberian Peninsula for the sea.

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Cape Roca (English: Cape Roca, Portuguese: Cabo da Roca) is the cape of Portugal adjacent to the Atlantic Ocean. It is a narrow cliff with an altitude of about140m, which is the western end of sintra Mountain. It is located at 38 degrees 47 minutes north latitude and 9 degrees 30 minutes west longitude, about 40 kilometers away from Lisbon, at the westernmost tip of Portugal and the westernmost tip of the whole Eurasia. People built a lighthouse and a cross facing the sea on the cliff in Cape Roca. There is a famous saying written on the tablet in Portuguese: "The land ends here and the sea begins in Sri Lanka" (Onde a terra acaba e o mar come? A: Cape Roca was once rated as one of the "50 Most Worth Visiting Places in the World" by netizens.