shadow city
noun[C]
ukusanareaof acitythat a verylargenumberofpeoplewho havetravelledthere toworkareliving, and theplacesthat theylivein, which are not usuallyhousesbuttemporarystructuresmade ofwood,cloth,plastic, etc.:
Thousands ofdisplacedpeoplefloodedin from theruralareas,formingashadowcitythatstretchedalong theriver.