The 13 foot Obelisco was erected at the entrance of Matriz Square in 1948 to commemorate the 100th anniversary of being declared a city. In 1848, the town’s previous name of Manaus was changed to Cidade da Barra do Rio Negro. In Portuguese, this means City of the Margins of the Black River. Now that was a mouthful! Eight years later, the city reverted back to being called Manaus.