Niagara Regional Road 681

Infobox road
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state=
highway_name=Niagara Regional Road 681
name_notes=
type=
route=
alternate_name=William Street
King Street
maint=the Niagara Region transportation department
section=
length_km=0.3
length_round=
length_ref= [http://maps.google.ca/maps?saddr=St+Paul+St+E+%26+William+St,+St+Catharines,+ON&geocode=&dirflg=&daddr=King+Street+and+Ontario+Street&f=d&hl=en&sll=43.15589,-79.24547&sspn=0.00947,0.019677&ie=UTF8&z=18&om=1]
length_notes=
established=
decommissioned=
direction=North/South
direction_a=North
terminus_a=Ontario Street (Regional Road 42)
beltway_city=
junction=
direction_b=South
terminus_b=St. Paul Street
counties=Niagara Region
rural_municipalities=
cities=St. Catharines
system=
previous_type=
previous_route=
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Niagara Regional Road 681 - named William Street and King Street - is a short regional road in Downtown St. Catharines. The route serves as the northbound one-way pair along with Ontario Street (Regional Road 42) which serves southbound traffic.

Regional Road 681, despite its number, no longer connects to Regional Road 81. Regional Road 81 was downloaded through the downtown core in 2002. Regional Road 681 now begins 80m east from where the western segment of Regional Road 81 ends. Prior to 2002, the King Street portion of the route was formerly numbered Regional Road 581. This section was re-designated 681 upon the truncation of 581.