AMP: 3
Location: Boston Rd and Chelmsford Rd, Billerica
Reassurance shield for Route 3A as 129 joins it.
AMP: 3
Location: Boston Rd and Treble Cove Rd, Billerica
Reassurance shield for 3A just around the corner from the last one.
AMP: 4
Location: Boston Rd and Floyd St, Billerica
Shortly thereafter, turn left for 129 east to Reading and Wakefield. Stay straight to stay on 3A south.
N to MA 110, S to MA 62
N to MA 129, S to MA 62
N to MA 110, S to MA 129
