Ahu Akahanga on the East coast of Easter Island is one of the Ahu which has been left as it was after the Rapa Nui (indigenous people of Easter Island), knocked all the Moai off their Ahu in the 18th and 19th century. European accounts in 1722 (Dutch) and 1770 (Spanish) reported seeing only standing statues, but by James Cook's visit in 1774 many were reported toppled. The huri mo'ai - the "statue-toppling" - continued into the 1830s as a part of internal conflicts among islanders. By 1838, the only standing moai were on the slopes of Rano Raraku and Hoa Hakananai'a at Orongo. In about 60 years, islanders had for some reason (possibly civil struggle between tribes) deliberately damaged this part of their ancestors' heritage. In modern times, moai have been restored at Orongo, Ahu Tongariki, Ahu Akivi and Hanga Roa. Most of the restoration work was carried out by a Japanese crane company, Tadano.