N.Y. GCT Law § 26

§ 26. Official map, establishment. Every city by ordinance, local law\nor resolution of the legislative body which has the authority to lay\nout, adopt and establish streets, highways and parks may establish an\nofficial map of the city showing the streets, highways and parks\ntheretofore laid out, adopted and established by law. Drainage systems\nmay also be shown on this map. Such map is to be deemed to be final and\nconclusive with respect to the location and width of streets, highways,\ndrainage systems and the location of parks shown thereon. Such official\nmap is hereby declared to be established to conserve and promote the\npublic health, safety and general welfare. Said ordinance, local law or\nresolution shall make it the duty of some appropriate official or\nemployee of said city at once to file with the clerk or register of the\ncounty or counties in which said city is situated a certificate showing\nthat the city has established an official map.\n