The first of 70 new Amtrak locomotives rolled off a Sacramento assembly line Monday, and it will begin operating this fall on the Northeast Corridor and the Keystone Corridor between Philadelphia and Harrisburg.

The electric "Cities Sprinter" locomotives, being built by Siemens Rail Systems for $466 million, will replace locomotives that have been in service for 25 to 35 years. Amtrak borrowed the money from the Federal Railroad Administration and says it will repay the money from NEC revenues.

The locomotives are designed to be more energy efficient than the existing fleet, but they will not travel at higher speeds. On the Northeast Corridor, they will travel up to 125 miles per hour, and on the Keystone Corridor, up to 110 miles per hour. - Paul Nussbaum