since when is the route in use?
In 1908, the New York State Legislature created Route 14, an unsigned legislative route.
New York State Route 64
In 1908, the New York State Legislature created Route 14, an unsigned legislative route that extended from Corning to Rochester via South Bristol and Pittsford. 
which places are connected by new york state route 64? It  serves as a connector between the southeastern suburbs of the city of Rochester and the Canandaigua Lake area, home to Bristol Mountain Ski Resort.
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New York State Route 64 [SEP] History
In the mid-1950s, NY 96 was realigned onto the new Eastern Expressway from Bushnell's Basin to NY 31F near East Rochester. From there, NY 96 followed modern NY 31F west to East Avenue, where it rejoined its original alignment. The portion of NY 96's original surface routing between the village of Pittsford and what is now NY 31F became part of an extended NY 64. A northwest extension of the freeway to what is now the Can of Worms was completed as a realignment of NY 96, resulting in another extension of NY 64 along East Avenue to the eastern edge of Rochester.