Passenger trains

The main passenger railroad in the United States is Amtrak (National Railroad Passenger Corporation), which operates over 300 trains carrying over 85,000 passengers daily. Amtrak's rail network serves over 500 destinations in 46 states, the District of Columbia, and the Canadian provinces of Quebec, British Columbia, and Ontario. It has been in operation since 1971, and has 21,300 miles of routes. 

Amtrak Routes
Route  Terminus 1 Terminus 2 Length Major Cities Served
 Acela Express Boston, MAWashington, D.C. 456 miles Boston, New Haven, New York, Philadelphia, Baltimore, Washington, D.C. 
 AdirondackMontreal, QCNew York, NY381 miles Montreal, Albany, New York 
 Amtrak Cascades Vancouver, BC Eugene, OR 467 milesVancouver, Seattle, Tacoma, Portland, Salem, Eugene 
 Auto TrainLorton, VASanford, FL855 miles Washington, D.C., Orlando,  
 California ZephyrChicago, IL  Emeryville, CA2,348 miles Chicago, Omaha, Lincoln, Denver, Salt Lake City, Reno, Sacramento, Bay Area
 Capitol CorridorAuburn, CA  San Jose, CA168 miles Sacramento, Bay Area 
 Capitol Limited Washington, D.C.Chicago, IL  764 milesWashington, D.C., Pittsburgh, Cleveland, Chicago 
 Cardinal New York, NYChicago, IL 1,146 miles  New York, Washington, D.C., Cincinnati, Indianapolis, Chicago
CarolinianNew York, NY Charlotte, NC  704 miles New York, Raleigh, Greensboro, Charlotte
 City of New Orleans Chicago, IL New Orleans, LA 934 miles Chicago, Memphis, New Orleans
 Coast Starlight Seattle, WA Los Angeles, CA1,377 miles Seattle, Portland, Los Angeles 
 Crescent New York, NY New Orleans, LA 1,377 milesNew York, Atlanta, New Orleans 
 Downeaster Boston, MABrunswick, ME 145 miles Portland (ME), Boston 
 Empire Builder Chicago, IL Portland, OR/Seattle, WA 2,206/2,257 milesChicago, Milwaukee, St Paul/Minneapolis, Spokane, Portland/Seattle 
 Empire Service New York, NY Niagara Falls, NY460 miles  New York, Albany, Syracuse, Rochester, Buffalo
 Ethan Allen Express New York, NY Rutland, VT 241 miles New York, Albany
 Heartland Flyer Oklahoma City, OK Fort Worth, TX 206 miles Oklahoma City, Fort Worth
 Hiawatha Milwaukee, WI Chicago, IL 86 milesMilwaukee, Chicago 
 Hoosier State Chicago, IL Indianapolis, IN196 miles Chicago, Indianapolis 
 Illinois ServiceChicago, IL  Quincy/Carbondale, IL
St Louis, MO
 Varies Chicago, St Louis
 Keystone New York, NY/Philadelphia, PA Harrisburg, PA 195 miles New York, Philadelphia, Harrisburg
 Lake Shore Limited Chicago, IL New York, NY/Boston, MA
 959/1,017 miles New York/Boston, Albany, Syracuse, Springfield, Erie, Cleveland, Toledo, Chicago
 Maple LeafNew York, NY Toronto, ON  544 milesToronto, Niagara Falls, New York 
Michigan Services  Chicago, IL Port Huron/Grand Rapids/Pontiac, MI Varies Chicago, Grand Rapids, Detroit
 Missouri River Runner Kansas City, MO St Louis, MO 283 milesSt Louis, Kansas City 
 Northeast Regional Boston/Springfield, MA Norfolk/Richmond/Newport News/Lynchburg, VA 664 miles Boston, Providence, Springfield, Hartford, New York, Washington, D.C., Richmond, Newport News/Virginia Beach
 Pacific Surfliner San Luis Obispo, CASan Diego, CA  350 miles Santa Barbara, Los Angeles, San Diego
Palmetto New York, NYSavannah, GA  829 milesNew York, Philadelphia, Baltimore, Washington, D.C., Richmond, Raleigh, Charleston, Savannah 
 Pennsylvanian New York, NY Pittsburgh, PA 444 milesNew York, Pittsburgh 
Piedmont  Raleigh, NC Charlotte, NC173 miles Raleigh, Charlotte 
San Joaquin  Bakersfield, CAOakland/Sacramento, CA  315/282 milesBay Area, Sacramento, Bakersfield 
 Silver Service New York, NY Miami/Tampa, FL 1,500 milesNew York, Philadelphia, Baltimore, Washington, D.C., Richmond, Raleigh, Charleston, Savannah, Jacksonville, Orlando, Tampa, Miami 
Southwest Chief  Chicago, IL Los Angeles, CA2,265 miles Chicago, Kansas City, Albuquerque, Los Angeles 
 Sunset LimitedLos Angeles, CA New Orleans, LA 1,995 miles New Orleans, San Antonio, Los Angeles 
 Texas Eagle Chicago, ILSan Antonio, TX/Los Angeles, CA  1,306/2,728 miles Chicago, St Louis, Dallas, San Antonio, Los Angeles
Vermonter St Albans, VT  Washington, D.C.611 miles Burlington, Springfield, New York, Washington, D.C. 

Longest Routes
 Route Length
 Texas Eagle 2,728 miles
California Zephyr 2,348 miles 
 Southwest Chief 2,265 miles
 Empire Builder 2,257 miles
Sunset Limited  1,995 miles

Busiest Stations (2011)
 StationTotal Ridership 
New York, NY  9,493,414
 Washington, D.C.5,013,991 
 Philadelphia, PA 4,068,540
 Chicago, IL3,483,313 
Los Angeles, CA  1,657,446

Largest Host Railroads for Amtrak Trains (2011)
 RailroadLength
 BNSF Railway 6,800,000 miles
 Union Pacific Railroad6,000,000 miles 
 CSX Transportation 5,900,000 miles
 Norfolk Southern Railway 2,500,000 miles
Canadian National Railway 1,400,000 miles 

Amtrak Map

Sources
http://web.archive.org/web/20140407233045/http://www.amtrak.com/servlet/ContentServer?c=Page&pagename=am%2FLayout&cid=1246041980246
http://www.amtrak.com/train-routes
http://www.citylab.com/commute/2014/06/the-triumphant-return-of-private-us-passenger-rail/372808/
http://en.wikipedia.org/wiki/Rail_transportation_in_the_United_States
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