Editing Markham, Ontario (section)

===Roads===
{{Main|List of regional roads in York Region, Ontario}}

==== Road network ====
Markham's road network is based on the concession system. In 1801, Markham was divided into 10 [[Concession road|concessions]], with a north–south road separating each one. The concessions were further divided by a number of east–west sideroads. This formed a [[grid plan]] road network, with an intersection occurring approximately every two kilometers. Even though some of these roads have been realigned, Markham's present road network for the most part still follows the original grid plan.

Markham's concession (north–south) arterial roads are listed below, ordered from west to east (former numbers in parentheses):

* {{jcon|York|1|notext=y}} [[Yonge Street]]
** Boundary with the City of Vaughan
* {{jcon|York|34|notext=y}} [[Bayview Avenue]]
* {{jcon|York|12|notext=y}} Leslie Street
* {{jcon|York|8|notext=y}} [[Woodbine Avenue]]
* {{jcon|York|65|notext=y}} Warden Avenue (5th Concession Road)
* {{jcon|York|3|notext=y}} Kennedy Road (6th Concession Road)
* {{jcon|York|67|notext=y}} McCowan Road (7th Concession Road)
* {{jcon|York|68|notext=y}} Markham Road (8th Concession Road)
** Continues as {{jcon|hwy|48|shield=y|notext=y}} [[Ontario Highway 48|Highway 48]] north of Major Mackenzie Drive
* {{jcon|York|69|notext=y}} Ninth Line (9th Concession Road)
* {{jcon|York|48|notext=y}} [[Donald Cousens Parkway|Donald Cousens Parkway / Markham By-pass]]
** Signed as a regular road south of Box Grove By-pass
* Reesor Road (10th Concession Road)
* Eleventh Line (11th Concession Road)
* {{jcon|York|30|notext=y}} York-Durham Line
** Boundary with the [[Pickering, Ontario|City of Pickering]]

Reesor Road and Eleventh Line are the only north–south roads that are not fully regional roads. These two roads are rural routes with very few homes and minimal traffic. Eleventh Line ends just south of Highway 407 with the road rerouted (old section fenced off with partial gravel bed) to intersect with York-Durham Line. Areas east of Donald Cousens Boulevard either serve new residential developments or are largely rural and/or agricultural.

Markham's sideroad (east–west) arterials are listed below, ordered from south to north (former numbers in parentheses):

* [[Steeles Avenue]]
** Original Scarborough Townline, boundary with the [[Toronto|City of Toronto]]
* {{jcon|York|71|notext=y}} 14th Avenue
** Continues west of {{jcon|York|65|notext=y}} Warden Avenue as Alden Road
*** Continues west of Rodick Road as Esna Park Drive
**** Continues west of {{jcon|York|8|notext=y}} Woodbine Avenue as John Street
* {{jcon|York|7|notext=y}} Regional Road 7 (formerly 15th Avenue)
** Continues as {{jcon|hwy|7|shield=y|notext=y}} [[Ontario Highway 7|Highway 7]] east of Reesor Road
* {{jcon|York|73|notext=y}} 16th Avenue
* {{jcon|York|25|notext=y}} Major Mackenzie Drive East (17th Avenue)
* {{jcon|York|49|notext=y}} Elgin Mills Road East (18th Avenue)
** Signed as a standard road east of Victoria Square Boulevard
* 19th Avenue
** Boundary with the [[Whitchurch-Stouffville|Town of Whitchurch-Stouffville]]

==== Important thoroughfares ====
Major highways that pass through Markham include [[Ontario Highway 404|King's Highway 404]] (from Toronto to just south of Lake Simcoe), which marks Markham's boundary with the [[Richmond Hill, Ontario|City of Richmond Hill]], and the [[407 ETR]] (more commonly known as Highway 407), a privately owned [[Toll road|toll highway]] that passes north of Toronto and connects Markham with [[Burlington, Ontario|Burlington]] and [[Oshawa]]. Highway 404 is one of the most important routes used for travel to and from the City of Toronto. Highway 407 primarily serves Markham from [[Yonge Street]] to [[York-Durham Line]]. The highway connects Markham with [[Clarington]] to the east, and [[Burlington, Ontario|Burlington]] to the west.

One of the most heavily travelled arterial roads in Markham is Regional Road 7, a major east–west artery. This road is more commonly referred to as [[Ontario Highway 7|Highway 7]], a name which comes from the time when it used to be a [[Ontario Provincial Highway Network|provincial highway]]. The road is still officially Highway 7 east of Reesor Road. Other major east–west routes include [[York Regional Road 73|16th Avenue]], [[York Regional Road 25|Major MacKenzie Drive]], the combination of John Street/Esna Park Drive/14th Avenue, and [[Steeles Avenue]] which forms Markham's southern boundary with Toronto.