A good starting point...Bike Maps - Bike Madison - City of Madison, Wisconsin

If you like hills, drive about an hour west of Madison (Dodgeville/Mount Horeb area) for some challenging stuff.
Bike Routes near Mount Horeb/Bluemounds State Park | MapMyRide

Or go north to Devil's Lake State Park near Baraboo. Beautiful challenging riding, although not as tough as the Bluemounds/Dodgeville/Mount Horeb area. Bike near the Wisconsin River by Prairie du Sac. You won't regret it. Plenty of touristy stuff if that's your thing.

Or make a run to one of the breweries. If you like beer, you can't go wrong with the New Glarus Brewery which is SSW of Madtown. It'd be in your 50-ish mile range depending on where you're staying.