March 12, 2004 -- On Thursday, March 11, ten bombs exploded on commuter railway trains in Madrid, killing almost 200 people and injuring more than 1,400. The attack was Europe's deadliest since World War II.

At the time of this writing, ETA, the violent Basque separatist group had denied responsibility for the attack. An Islamic group sent a letter to a London newspaper Thursday claiming responsibility, but Time magazine noted that the "Abu Hafs al-Masri Brigade" has previously claimed responsibility for other things they didn't do.

What does this mean for travelers? Anyone currently in Spain should expect massive public demonstrations and potential disruptions as Spaniards show their solidarity against terrorism. RENFE, the Spanish national rail system, says only a few commuter train lines have been disrupted; all long-distance services into and out of Madrid, including commuter trains to Aranjuez and Toledo, are running.

(The New York Times also reported that several US rail agencies, including Amtrak and the local agencies in New York and Chicago, had stepped up security, but in ways that travelers probably wouldn't notice.)

In an announcement ( issued Friday evening, the US State Department says Americans should "remain alert and avoid large crowds" -- but stops well short of telling Americans not to visit Spain, or to leave the country.

The advisory offices of Australia (, Canada ( and the UK ( are more on the ball; all three have changed their reports on Spain to mention the attack. None of the three countries is advising its travelers to leave or avoid Spain. They do say to avoid demonstrations and large public gatherings, and to "exercise caution" -- a good thing to do in any case.

Professional risk analysts Air Security International ( are monitoring the situation in Madrid; they are also not advising that travelers leave Spain.

Obviously, expect things to be tense in Madrid. It's fair to say that you should expect security delays through Madrid's airports and train stations, but don't let this tragedy deter you from traveling to Spain.

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