Book your ticket through Rail Europe by visiting the Web site (see Resources) or calling a North American agent at (888) 382-RAIL.
Log on to the European Rail Web site to review the departure times for the trip and book your trip to Romania via the Internet. Though this is a good way to get timetables, it will likely be easier to book the actual ticket at the Sirkeci station in Istanbul. The ticket will cost around 59 Turkish Lira with a supplement of 17 to 24 YTL for a sleeper.
For more information, call European Rail at 011 (+44) 20 7387 0444. (From outside of the United States and Canada, call 00 (+44) 20 7387 0444.)
Get off the train at Vedele station in Romania if you plan on continuing on to Budapest, Vienna or further. Though the timetable makes it seem as if you'd have time to stop in Bucharest, you most likely will not because of the habitual tardiness of the train.
Keep your passport and travel documents close at hand during the trip. You'll have to exit the train and get your passport stamped at the border in Kapikule.
Confirm your transportation to Istanbul before you try to go further in the booking process. There is only 1 train per day from Istanbul to Bucharest (the capital of Romania) so you need to make sure you arrive in Istanbul with time to spare.
Decide where you will be beginning your journey from Turkey. No matter where you begin, you'll ultimately travel through Istanbul but the trip to Istanbul will vary in time and price depending on where you are coming from.
Review your trip plan and decide if you want to travel directly to Romania or if you'd like to break the trip into segments to allow more time for exploration.
Look at rail pass options to see if a multi-day pass would better suit your travel needs than a standard point-to-point ticket. Passes such as the Eurail will work on the Bosfor Express.