Originally Posted by thecrunge

Hi, I live in southern Ontario and can give you a good route. The only way I know to give this route is to write it all out; you could follow along my route on Google maps. I've ridden on all of these roads, so they'll mostly be very bike-friendly, paved (or chip sealed) and as direct as possible. Okay, here goes.

In downtown Wasaga, from Mosley St., turn south on 45th St. S. (which might be a little busy) and follow for ~5km and make a left/right jog at Hwy 26, continuing south on Centre Line Rd. (should be much quieter)

-after ~13km turn left at Webster Rd.
-in ~1.5km turn right on concession Rd 2
-follow for ~9km and the road will turn left and will be called (Tosorontio) sideroad 17
-follow 2.5km and turn right at Concession Rd 4
-after 10 km, make a right/left at Hwy 89 continuing south on Conc. 4
-follow for ~1km
-turn left at (Adjala) 30 Sideroad, follow for ~1km to Conc. 5 and turn right
-follow for 12km south to Sideroad 10 and turn left
-go ~1.5km west to County Rd 50 (road construction) and make a left/right onto County Rd 14
-follow for 3km to Adjala/Tecumseth townline and turn right (Hamlet of Colgan)
-after ~0.5km turn left, still going west on C.R. 14 (a.k.a. 5 Line)
-go for ~12km (passing the north edge of Tottenham) and turn right at 20th Sideroad
-after about 5km cross Hwy 9 and continue south into Schomberg
-follow Main St which will curve left to Hwy 27
-turn right at 27 and go 0.5km to Lloydtown Aurora Rd (C.R. 16) and turn left
-follow for ~8km (over Hwy 400) to Jane St and continue straight onto Kettleby Rd
-after 2km turn right at Keele St
-go south 3km to Sideroad 17 and turn left
-follow for 2km to Snowball corners (yes Snowball...) and make a left/right onto Wellington St (starting to get a bit busy)
-go for another 2km to Bathurst St. and turn right
-go for yet another 2km to Henderson Drive and turn left
BTW, this is where you have to cross through a very populated vein north of Toronto, but won't last long.
-follow 2km to Yonge St (Aurora) and turn right
-immediately after the trainbridge turn left onto Industrial Pkwy S (going east)
-follow for ~1km and turn right onto Vandorf Sdrd.
-go a few km to Leslie St and turn left and stick to the right to continue east on Vandorf (over Hwy 404)
-keep heading east until McCowan Rd and turn right
-go 2km and turn left onto Bethesda Sdrd
-in another 2km turn right at Hwy 48 (busy) and in 0.5km turn left back onto Bethesda
-go 2km and turn left onto Ninth Line (Regional Rd 69) and turn left
-after a half km turn right back onto Bethesda (east)
-follow for a few km right up to York Durham Line and turn right
-take for 1km and turn left onto Uxbridge-Pickering Townline
-follow for ~8km to Hoxton St and turn right
-after 1km turn right onto Old Brock Rd heading south through Claremont village
-continue down to Brock Rd (C.R. 1, busyish) and turn right (south)
-in 4-5km turn left onto Conc.Rd 7 (31)
-take for ~7km and turn right at Lakeridge Rd
-after a half km turn left onto Columbus Rd W
-follow for 11km to Ritson Rd N and turn right
-follow for 6km and turn left at Conlin Rd E (north edge of Oshawa)
-take Conlin for 8km to Solina Rd and turn right (south)
-follow for 9km to Nash Rd and turn left
-take for ~5km to Martin Rd (57) and turn right
-take for half km south and turn left at Longworth Ave (Bomanville)
-follow for a few km to Mearns Ave and turn right
-after 1.5km turn left at Concession St E.
-continue past Darlington-Clarke Townline where the name changes to Conc Rd 3 and turn right at Arthur St (1km east of Hwy 35/115)
-a few km on Arthur will take you into Newcastle, then turn right onto King St E (heading west for a bit)
-in a half km turn left onto Mill St S.
-follow south over Hwy 401 and shortly you'll officially (and finally) be on the Waterfront Trail (Lakeshore Rd)

I know this will be too much, and alot of stair stepping, but it really is the quickest and quietest way through the busy mess that is the GTA. So, there you go and have a safe and fun trip!