| Illinois Railway Museum http://www.mcs.net/~devanno/irm.html |
| Illinois Western Railroad Company http://www.illwestern.com |
| Imagita http://www.imagita.dk/eng_sider/f_index.html |
| Incertrans Bucharest http://www.incertrans.ro |
| Indian Railways (IR) http://www.indianrailway.com |
| Indian Railways (RAILWAY STAFF COLLEGE) http://www.rscbrc.ac.in |
| Indian Railways (unofficial) http://www.trainweb.org/indiarail |
| Information and Technology Center for Transport and Infrastructure (CROW) http://www.crow.nl |
| Information Research Network (IRN) http://www.irn-research.com/travel.html |
| Information System of German Transport Security Council http://www.bg-dvr.de |
| Information technology in the transportation indus http://www.ttpnews.com |
| Infrastructure Interaction VI (VEHICLE) http://www.engfnd.org/9bn.html |
| Inlandsbanan AB, Sweden http://www.inlandsbanan.se/ |
| Innotrans http://www.innotrans.com |
| Institut Management Transport Logistique, University Paris XII http://www.univ-paris12.fr/www/senart/imtl/ |
| Institute for Transport Studies, Leeds http://www.its.leeds.ac.uk |
| Institute of Railway Studies http://www.york.ac.uk/inst/irs/ |
| Institute of Transport (CIP) http://www.sicip.co.yu |
| Institute of Transportation Economics http://www.bekkoame.or.jp/~ite/index.html |
| Institute of Transportation Engineers, Washington (ITE) http://www.ite.org |
| Institution of Railway Signalling Engineers (IRSE) http://www.irse.org |
| Instituto Argentino de la Energía General Mosconi (IAE ) http://www.iae.org.ar |
| Instituto Ferrocarriles del Estado de Venezuela (IFE) http://www.ife.gov.ve |
| Instituto Mexicano de Transporte (IMT) http://www.imt.mx/English/index.html |
| Inter Rail (ISTED ) http://www.isted.3ct.com/PUBLI/INTERAIL/rail.htm |
| Intermodal Association of North America (IANA) http://www.intermodal.org |
| Intermodal transport Web site (IMPREND PROJECT) http://www.intermodaltransport.com/ |
| International Association for Bridge and Structural Engineering (IABSE) http://www.iabse.ethz.ch/ |
| International Bridge, Tunnel and Turnpike Association (IBTTA) http://www.ibtta.org |
| International Cargo Handling Co. http://www.ichca.org.uk |
| International Department of Ukrainian Railways (UZ) http://ci.uz.gov.ua |
| International Institute of Rail Electrification http://www.geocities.com/pres_iiree/index.htm |
| International Rail Transport Committee (CIT) http://www.cit.ch |
| International Road Union (IRU) http://www.iru.org/Services/Indice.E.html |
| International Telecommunications Union (ITU) http://www.itu.ch |
| International Transport Journal http://www.rittmann.ch |
| International Transport Journal http://www.transportjournal.com/ |
| International Transport Workers Organisation (ITF) http://www.itf.org.uk |
| International Union of Railways (UIC) http://www.uic.asso.fr |
| Internet Railroad Directory (RAILSERVE) http://www.railserve.com |
| InterRail News http://interrail.publinet.it |
| Intrans (CSKD) http://www.intrans.cz |
| Irish Rail (IARNROD EIREANN) http://www.irishrail.ie/ |
| ISO http://www.iso.ch |
| Israel Ports & Railways Authority http://www.israports.org.il |
| Israel Railways (ISR) http://www.israrail.org.il |
| Italferr http://www.italferr.it |
| Italian Highspeed Trains (TAV) http://www.tav.it |
| ITS in Japan http://www.nihon.net/ITS/ |
| ITS International http://www.itsinternational.com |
| ITS On Line http://www.itsonline.com |