Route 100
Route information
Maintained by New Brunswick Department of Transportation
Length	48.58 km[1] (30.19 mi)
Existed	1976–present
Major junctions
West end	Route 1 in Lorneville
East end	Route 1 in Hampton
Location
Country	Canada
Province	New Brunswick
Major cities	Saint John, Rothesay, Quispamsis, Hampton
Highway system
Provincial highways in New Brunswick Former routes
← Route 95 → Route 101

Route 100 is 49 kilometres long, and runs from Saint John to Hampton, New Brunswick.

Route 100 follows the through route across Saint John and the Kennebecasis Valley that was used prior to the construction of the Saint John Throughway and MacKay Highway. The road begins on Saint John's west side using Ocean West Way and Fairville Boulevard, and crosses the Reversing Falls Bridge to Chesley Drive on the north end. It then crosses a viaduct to the city centre, where it takes City Road to the east side, and leaves Saint John on Rothesay Avenue. Route 100 continues as the Hampton Highway through the Kennebecasis River Valley towns of Rothesay and Quispamsis, and uses a former alignment of Route 1 to reach Hampton.