Are you on Strava? One nice feature is that is allows you to search for rides. I just punched in 20-50 miles, road bike, and it gives a list of rides. You can refine the search by altitude, etc, or just click on rides until you find something that looks good.

Example - Strava | Activity Search[country]=United+States&[state]=New+Jersey&[city]=Cherry+Hill&[lat_lng]=39.926813%2C-75.02463119999999&keywords=&activity_type=Ride&type=road&distance_start=20&distance_end=50&time_star t=0&time_end=10&elev_gain_start=0&elev_gain_end=15000