, ▁p aved ▁and ▁w iden ed ▁streets , ▁and ▁marked ly ▁improved ▁health ▁conditions , ▁not ably ▁by ▁reducing ▁cases ▁of ▁yellow ▁fe ver ▁and ▁small po x . ▁The ▁central ▁a venue ▁( called ▁Aven ida ▁Rio ▁Bran co ▁from ▁ 1 9 1 2 ) ▁was ▁opened ▁during ▁that ▁period ; ▁Aven ida ▁Be ira - Mar , ▁running ▁parallel ▁to ▁part ▁of ▁the ▁south ▁shore , ▁was ▁built ▁on ▁rec laimed ▁land ▁and ▁several ▁other ▁important ▁a ven ues ▁were ▁opened . ▁ ▁The ▁population ▁of ▁the ▁Federal ▁District ▁exceed ed ▁ 1 , 0 0 0 , 0 0 0 ▁by ▁ 1 9 2 0 ▁and ▁increased ▁to ▁ 1 , 7 5 0 , 0 0 0 ▁by ▁ 1 9 4 0 . ▁During ▁that ▁period ▁the ▁number ▁of ▁industrial ▁establish ments ▁in ▁the ▁Federal ▁District ▁nearly ▁tre bled . ▁Castle ▁Hill ▁was ▁demol ished , ▁land ▁re clam ation ▁increased ▁the ▁area ▁in ▁the ▁Centro , ▁and ▁the ▁first ▁sk ys c rap ers ▁appeared . ▁Street car ▁lines , ▁now ▁moved ▁by ▁elect rical ▁power , ▁multip lied . ▁While ▁settlement ▁spread ▁on ▁the ▁east ▁coast , ▁some ▁areas ▁to ▁the ▁north ▁lost ▁status , ▁such ▁as ▁São ▁Crist ó v ão , ▁which ▁became ▁an ▁industrial ▁and ▁lower - class ▁resident ial ▁neighbourhood . ▁ ▁In ▁the ▁mid - 2 0 th ▁century , ▁metropol itan ▁Rio ▁de ▁Janeiro ▁grew ▁beyond ▁its ▁formerly ▁narrow ▁conf ines ▁because ▁of ▁migration ▁from ▁other ▁parts