 The Galápagos tortoise or Galápagos giant tortoise ( Chelonoidis nigra ) is the largest living species of tortoise . Modern Galápagos tortoises can weigh up to 417 kg ( 919 lb ) . Today , giant tortoises exist only on two remote archipelagos : the Galápagos 1000 km due west of Ecuador , and Aldabra in the Indian Ocean , 700 km east of Tanzania . 
