The highway follows a 310 km (190 mi) route along the southern coast of the Bay of Fundy through the Annapolis Valley, the largest agricultural district in the province. Between its western terminus at Yarmouth to Weymouth, the highway is 2-lane controlled access. Between Weymouth and Digby, the highway reverts to a 2-lane local road. From Digby to Grand Pre, the highway is 2-lane controlled access. From the Gasperaux River crossing near Grand Pre to 3 km west of Exit 6 (Falmouth) the highway is a 4-lane expressway. Heading east the highway is 2-lane controlled access until Exit 5 (Trunk 14). From Three Mile Plains to its eastern terminus at Bedford, the highway is a 4-lane expressway. Some of the 2-lane controlled access sections of the highway are actually 3 or 4 lanes, with the addition of passing lanes. One section of the 4-lane expressway near Hantsport is actually a short 5-lane (3 lanes westbound) section for about 2 km due to previous road configuration for a passing lane due to a steep hill.
The provincial government named the highway the Harvest Highway on 7 December 2008 to recognize the important contributions of farmers in Nova Scotia.
The highway has developed in sections, with the part between Bedford and Windsor having been built in the 1970s, followed by parts through the Annapolis Valley and Digby and Yarmouth counties in the 1980s–1990s. The highway was built largely to replace the Dominion Atlantic Railway service in the communities along its route. As a result the highway serves as a "B-Train" route for the area.