Be sure to check out the guidelines for items that are permitted or prohibited on airlines from the Transportation Security Administration before your trip.
https://www.tsa.gov/travel/security-screening/whatcanibring

Check out the weather for your travel destination.
https://weather.com/

Calculate the exchange rate from dollars to Euros, or any other currency you may need for your destination.
http://money.cnn.com/data/currencies/

Find out about customs regulations and obtaining passports and visas by visiting www.state.gov/travel/ and/or about travel advisories at www.travel.state.gov/traveladvisories