ShorelineEastMetro-North (http://www.mta.info/)

Metro-North goes through two counties in the state of Connecticut--New Haven and Fairfield.  Metro North’s New Haven line, has three branch lines--the New Canaan, Danbury, and Waterbury--72 miles to New Haven.

The railroad's hours of operation are approximately 4 AM to 3:40 AM. Service intervals vary according to destination and time of day. First trains arrive in Grand Central at 5:30 AM and the last trains leave the terminal at 2 AM. Weekdays, peak-period trains east of the Hudson River run every 20-30 minutes; off-peak trains run every 30-60 minutes; and weekend trains run hourly.

To view schedules, click here: http://as0.mta.info/mnr/schedules/sched_form.cfm

Shore Line East (http://www.shorelineeast.com/)

Shore Line East (SLE) is a rail service providing access between New London and New Haven seven days a week. Shore Line East THRU (express) service is also available weekdays to/from West Haven, Bridgeport and Stamford. Connections to Metro-North’s New Haven Line and Amtrak are available at New Haven's Union Station.

Shore Line East provides access between New London and New Haven, with additional limited THRU (express) service to West Haven, Bridgeport, and Stamford Metro-North stations. Connections to Metro-North’s New Haven Line and Amtrak are available at New Haven's Union Station.

Shore Line East trains run seven days a week and on holidays. Service is primarily westbound (toward New Haven) in the morning and eastbound (toward Old Saybrook and New London) in the afternoon/evening.
To view schedules, click here: http://www.shorelineeast.com/schedules

Amtrak

The main line of the Northeast Corridor (NEC) is 457 miles long traversing major cities in the northeast region including Washington, DC, Baltimore, Philadelphia, New York and Boston. With the addition of connecting corridors to Harrisburg, PA, Springfield, MA, Albany, NY and Richmond, VA, the NEC spans a total of 899 miles. Most of the rail line is owned by Amtrak, with New York State, the Connecticut Department of Transportation and the Massachusetts Bay Transportation Authority owning parts of the northern section. The Northeast’s five major metropolitan regions – Boston, New York, Philadelphia, Baltimore and Washington, DC – rely on Amtrak services for a significant and growing share of business and leisure passenger travel – and on NEC infrastructure for the daily commuting needs of their workforces.

In addition to operating the Acela Express®, Northeast Regional, and Long Distance train services on the NEC, Amtrak serves as the infrastructure manager for the majority of the NEC. Amtrak provides dispatching services and electric propulsion power and maintains and improves the infrastructure and facilities used by commuter and freight rail services. The NEC is an incredibly intricate railroad system and one of the most complex and heavily-used railroad territories in the world. Amtrak is a minority user of the NEC but the only operator to provide end-to-end service.

To view schedules, click here: http://www.amtrak.com/northeast-train-routes