Amtrak discounts select 1-way Northeast Regional fares, with prices starting at $11, as seen on Travelzoo. (Scroll down to see all of the available routes.) This price is based on fares departing from Boston (BOS) with arrival in Providence, RI (PVD) on May 11. Blackout dates apply and a 2-week advance purchase is required. Book this travel deal by April 30. Other notable 1-way fares:

• Washington D.C. (WAS) to Baltimore (BWI) from $13
• New York (NYP) to Newark, NJ (NWK) from $23
• see all available Amtrak 1-way fares