Current intelligence suggests that al-Qa'ida and affiliated organizations have continued to plan attacks, and that they may use various methods and weapons to target both public and private interests.
The alert urges travelers, especially those near tourist sites and public transportation hubs, to "take every precaution to be aware of their surroundings and to adopt appropriate safety measures to protect themselves when traveling."
It is also suggested that U.S. citizens register any European travel plans with the Consular Section of the U.S. Embassy through the State Department's travel registration Web site.
Though the peak season for European cruising is past, smaller crowds actually make October one of the loveliest times to cruise the region. Despite chillier temperatures, many Americans seeking the most value from their European vacations tend to visit during this time of year, as prices are typically lower.
Additionally, Cunard's Queen Elizabeth -- one of the most highly anticipated ships of the year -- is set to debut later this month. The ceremony, at which the Queen of England herself will serve as godmother, will take place in Southampton, England. Though security is already expected to be exceptionally tight, threats of terrorism are likely to spark additional precautions.
To that end, Teijo Niemela, a Cruise Critic contributor who is covering the event, reports that he's shifted lodging plans. Originally he planned to bunk near Victoria Station, a major transportation hub, but has now decided to stay farther from London's center.
Cruise Critic members are already evaluating the ramifications of the alert, most agreeing that the show -- and the cruise -- must go on. For example, Quilt_Nurse says, "Travel, be cautious, and don't hide away in your house."
For more information, visit the U.S. Department of State's Web site.
We'll be sure to keep you posted, but for now, you can join the conversation here.
--by Shayne Rodriguez Thompson, Web Content Producer