The Iron Horse The first great change in the quiet rural life of Croton ( called Collabergh Landing when the Point was Teller's Point ) came with the advent of the steam engine in 1849 . Men employed by the New York Central Railroad Company made their homes in Croton . Transporta- tion facilties made it possible for people to work in New York and reside in a small rural community . Soon the railroad made Croton a commuting residential village . The Croton Dam The second great change affecting the village came a half century after the coming of the railroad . Between 1892 and 1905 , New York City built the famous Dam to con- serve all the waters in the chain of Croton Lakes . The structural and financial difficulties in the building of the Dam were many . After sev- eral years of trouble New York City engaged John Byron Goldsborough as engineer . Mr. Goldsborough com- pleted the Dam in 1905. The Croton Dam is the second largest hand hewn masonry job in the world ; it is exceeded only by the Great Pyra- mids of Egypt . During the building of the Dam it was necessary to import many artisans from Italy . Some of them returned to Italy with their earn- ings , but many made their homes in Croton - on - Hudson . Their chil- dren and grandchildren are num- erous in the village today . Annexation of Harmon The real estate development com- pany of Wood , Harmon and Com- pany purchased the farm which constituted the area known as Har- mon and laid it out in streets and lots in 1907. Lots were sold between 1907 and 1909 , and in 1909 a few houses were built . Wood , Harmon and Company maintained the streets , furnished water and elec- tricity and provided garbage col- lection .