Amtrak discounts select 1-way Northeast Regional and Keystone Service fares, with prices starting at $12, as seen on Travelzoo. (Scroll down to see all of the available routes.) That's a savings of at least 25% off on select coach fares. This price is based on fares departing from Boston (BOS) with arrival in Providence, RI (PVD) on June 12. Blackout dates apply and a 2-week advance purchase is required. Book this travel deal by May 23.