Route 21, also known as Bauline Line, is a 9.3-kilometre-long (5.8 mi) north-south highway on the Avalon Peninsula of Newfoundland in the Canadian province of Newfoundland and Labrador.

It serves to connect the towns of Torbay and Bauline.

It heads west past some parks, homes, and businesses for a few kilometres before leaving Torbay and continuing northwest through rural wooded areas.

The highway now enters Bauline and passes by some businesses before having an intersection with Pouch Cove Line.

Route 21 now winds its way down some hills into downtown, where it comes to an end at the Atlantic coast at Bauline’s harbour.