The obelisk marks the pre­cise cen­ter of the con­ti­nent, as cal­cu­lat­ed by leg­endary Brazil­ian explor­er Can­di­do Ron­don. A mark­er was first erect­ed at the site in 1909, and the obelisk was built in 1975. The site was orig­i­nal­ly an open field used for more than just bull­fight­ing, but as the area devel­oped, build­ings were filled in around it, and the obelisk now forms the cen­ter of a mod­ern gov­ern­ment plaza, anchored by the city coun­cil head­quar­ters. Years lat­er, with the advent of satel­lite map­ping, a more pre­cise geo­graph­ic cen­ter of the con­ti­nent was cal­cu­lat­ed, locat­ed just 28 miles from Ron­don’s orig­i­nal loca­tion.