As giants,our size is impressive. For instance, we can be up to 1.8m, or over 5 ft,in length and can weigh up to 400 kg or roughly 900 lbs. We don't stop growing until we're about 45 years old! Scientists believe that gaint tortoises once lived on most of the world's continents. While the Galapagos giant tortoises remain famous for their uniqueness, another species of giant tortoise lives on Aldabra Atoll, the world's second largest coral atoll, in the Indian Ocean.