On our Moms trip to Europe we traveled between cities using all available means . We traveled by plane (First Class and Coach) and Automobile. After an amazing African Dinner at Im Herzen Afrikas, we had a good sleep and it was time for an Early morning Train ride from, Frankfurt to Berlin. Generally, while on vacation, I like to travel between cities either early morning or late night. By traveling when you would normally be asleep, you maximize the time you spend at your destination.
Should I Travel from Frankfurt to Berlin by Train?
This is a question you should ask yourself before traveling between any two cities in Europe. Given how compact europe is, it has the widest variety of inexpensive transportation of anywhere I have ever traveled. To determine which you should utilize, consider cost, comfort, and efficiency. Typically, I weigh these options for each option.
Frankfurt to Berlin by Air
Flights from Frankfurt to Berlin generally start around 44€. While this isn’t bad for air travel, this does not include any baggage fees. Flights generally take slightly over an hour, but the process makes it highly inefficient. By the time you consider time for transport to the airport, getting through airport security, and transportation to the heart of the destination city, you are talking closer to 4-5 hours. As the highest cost and least efficient (with all the necessary additional time), I would strongly advise against air travel on such a short trip.
Frankfurt to Berlin by Bus
A FlixBus from Frankfurt to Berlin will run you at a minimum 9.99€ and will take about 5-6 hours depending on the routing. FlixBus, is a fairly comfortable and extremely low cost way to travel within Europe. Every bus has onboard Wifi (though ours from Colmar to Frankfurt did not function in Germany) and allows you to store 1 piece of luggage in the Bus’s cargo hold for free. One major benefit of FlixBus and trains over a plane is that they both drop you off in the city center.
Frankfurt to Berlin by Train
Train was our preferred method to travel for this route. If you book ahead of time you can book a train between Frankfurt and Berlin for about 20€. While twice the price of the FlixBus, with a train you have much more space and comfort than the FlixBus. German trains also have free wifi and I have never had to worry about its functionality. You also do not have to pay for baggage. At 4 hours and 15 minutes, the train is the quickest method, and unlike bus you do not have to worry about traffic.
All of these benefits make it worth the extra 10€ to take a train over the bus.
Booking
Before making any sort of train booking, I highly suggest checking out the man in seat 61. We are not affiliated with seat 61 in anyway, but I use this site all of the time. This travel site has helpful tips about the best ways to travel by train through Europe. It includes tips on the cheapest routes to take and the cheapest ways to book. Consulting Seat 61 before a train trip in Europe will usually save you significant time and money.
As this trip is completely within German borders booking is very straight forward. The simplest and cheapest way to book is through www.bahn.com. Booking through this site is booking through the German rail system directly. You do not have to pay any third party fees or surcharges and you will get the best prices. There is also a well translated english option which makes it easy for English speakers to book.
Frankfurt to Berlin By Train
We arrived at the train station at 5:55 AM, 20 minutes before our train was scheduled to leave. At most European train stations this is more than enough time to find your platform and board your train, but if you are an inexperienced traveler you should probably leave a bit more time. We found our platform and were on our train within 5 minutes.

We boarded our train and made our way to an unreserved set of four seats. On most trains you will have a choice of sitting at a set of two seats facing directly at the back of the seat in front of you or a set of four facing each other with a table between the rows. Even when not traveling in a group of four, I prefer the table. The seats on most European trains are significantly bigger than what you you get on a plane and better cushioned. When it comes to comfort train trumps (is it still okay to use this word in its traditional sense) plane anyday.

This train, and a lot of the German ICE trains had a dining car. However, as it was early in the morning and I was tired, I opted for a nap rather than exploring the train

The train itself went along as scheduled. We arrive at Berlin Central Station at 10:30 as scheduled. This gave us time to stop at our hotel prior to our 12:30 berlin tour.
Overall
When traveling between Frankfurt and Berlin, we decided to take a train. At 20€ a person is the perfect balance between efficiency, comfort, and price.