Trinidad hosts Trinidad Carnival, one of the Caribbean’s largest pre-Lenten festivals.
The celebration takes place mainly in Port of Spain and culminates on the Monday and Tuesday before Ash Wednesday. Its modern traditions developed from European pre-Lenten festivities and the creative practices of formerly enslaved Africans after emancipation in 1834.
Trinidad Carnival is known for masquerade costumes, steelpan music, calypso, soca, and energetic street processions. Major events include the selection of the Calypso Monarch, Panorama steelband competitions, and the large Carnival parade. “Mas” refers to masquerade, while “J'ouvert” begins before dawn and has its own traditions.
The answer is Trinidad, not Tobago: the two islands form the country of Trinidad and Tobago, but the internationally famous Carnival center is Trinidad, especially Port of Spain. Dates shift each year because Carnival follows the Christian liturgical calendar.