This (along with two other trails over the border) make for a great (and relatively easy) 1/2 day…read moretrip. Here is a description of the 30-mile ride I took this week - PASSPORT REQUIRED:
Park at North County Hospital on Prouty Rd. (Newport). Trail starts 200 feet east. Pick up the gravel trail heading north by Lake Mephremagog. Good conditions for Hybrid and trail bike tires. At the end of the trail, take a right onto the paved road (North Derby Rd.) Approx. 2 miles to the end, then left.
Pass through Canadian customs. Take a quick, few-hundred feet detour, east from the Customs house for a photo of Canusa St. dividing the US/Canada. Then back to the customs station and a right following Rt. 247 north for about 3/4 mile, past a large "Rediker" stone and a couple of banks, until you see the Tomifobia Nature Trail heading off to the right. The first mile of this 19-km trail isn't too scenic but it gets better very quickly.
I went about 5 miles down the trail, then turned around and came back to the marked road barrier at "Ch. de Stanstead" (Stanstead Rd.?). There's a pond to your right at this crossing. Left /southeast on Ch. de Stanstead for about 2 miles to its end, then left (east) on Rue Maple. (This Stanstead/Maple roads part is seriously uphill for a total of about 2.5 miles).
At the end of Rue Maple, you're in downtown Stanstead. Take a right (south) onto Rt. 143/Rue Dufferin heading back towards the US border. Just before the border, make a left on Boulevard Notre Dame, then a quick right on Baxter. A couple of blocks take you to the Haskell Library and Opera house, straddling the border. Park the bike on the Canadian side and walk around to the front door of the library which is on the US side. Make sure to take a tour for 5 bucks to see the opera house and the stripes on the floors that mark the border running through the building.
From the library, go back north on Rue Church, 1/4 mile to Blvd. Notre Dame (Rt. 247) and take a left (west). Cross Rt. 143 (large stone fountain will be on your left). After a quick down-hill (1/4 mile), bear to the right on Rue Passenger, following black on white signs for "Piste Cyclable de Stanstead" bike trail . It's a little hard to find, so best to look at a Google Map before leaving the library to get familiar. Basically it's up a short hill on Rue Passenger than downhill left. You'll see the trail to the right at a power substation. It's less than 5 minutes from Library to this trail by bike.
Follow this bike trail about 2 miles until it crosses Rt. 247, about a 1/4 mile from the border station you where you entered Canada. Go left (south) on Rt. 247, through US customs, then a quick right at the post office to follow your way back on N. Derby Rd. to the Newport Trail and the start of the ride.
The Tomifobia and Newport trails are both loaded with beautiful sites. The final trail (Piste Cyclable Stanstead) is more functional than beautiful, but was in excellent condition (hard-packed dirt) and kept me off the main road (Rt. 247) just to the south of the trail.
Enjoy!