The trail itself goes through 14 states. The average time it takes to complete it is 5-7 months.
Bonus facts:
It 2017 Joe McConaughy completed the trail northbound in 45 days, 12 hours and 15 minutes, self-supported.
In 2015 Heather Anderson completed the trail southbound in 54 days, 7 hours and 48 minutes, self-supported.
There is an extension of the trail, known as the International Appalachian Trail that crosses Maine, through Canada with sections continuing in Greenland, through Europe and into Marocco.
The Eastern Continental Trail extension goes south into Alabama to Florida.