I meant Morrisville, VT. This is the closest town in the US to the northern terminus that has regular public transportation (on weekdays). This is the cheapest way to/from the northern terminus, as it is only 35 miles away; Burlington is more like 75, and you are likely to pay accordingly. From Morrisville, a bus runs to Waterbury, connecting with commuter buses along I-89 ($4 to Burlington). You can also take Amtrak to Springfield and NYC.