The New Rochelle Loop (11 miles)
We’ve done this one several times from the store on Sunday mornings. It seems more complicated than it is. There’s a premium on staying off the main roads. A simpler version is here but note that even here you’d want to pick up part of the Leewood Loop to get back to stay off of a main road. In the simpler version, you can also continue on Leewood under the bridge and then head south along the Bronx River Parkway trail.
Again, this stuff is just a starting point.
One big hill: Paine Avenue (at about 4) but lots of smaller ones that you start to feel toward the end.