We liked this hotel. It was basic and in the centre of town. It was safe to stay here and walk around at night. It is across the road from the main train station which is very convenient. The man at the desk was lovely and very helpful. He really went out of his way for us to find free parking (as we hired a car). It was close to all main sites.
The room was spacious but basic.
One negative was when my partner was walking to the bathroom, he kicked his foot against the uneven entrace into the bathroom. He really hirt his foot. So be mindful to be careful of this step. Other than that, it was a great stay! I would recommend it to anybody.

I stayed at the Hotel National for one night while in Frankfurt. I picked the hotel due to finding only bad reviews for hostels in Frankfurt - this hotel had the same prices but much better reviews, so I went with it instead. The price was terrific, and I was pleasantly surprised by the quality of the hotel for the price we paid. The staff at check-in were very friendly, and the interior of the hotel was quite nice. Our room was clean, spacious for European standards, and very comfortable. While the proximity to the train station was a huge plus, the only negative thing we experienced was some noise in the room due to traffic outside. It wasn't bad, however, and I had no trouble sleeping. Definitely recommended for students or couples looking for a nice but inexpensive place to stay.

Helpful hotel, located for an interesting nightlife, over the road from the main station, nice staff and enjoyed my stay. Internet 5 euro for 12 hours, internet Cafe over the road great for quick cheap connection.

My wife and I previously stayed at the National Hotel in December 2008 and returned for a few days in July 2010 following a pleasant initial stay. Unfortunately, this time we struck a period of very hot weather and discovered to our surprise that there is no airconditioning in the rooms (NOTE: This appears to be the case with many hotels of a similar rating in Frankfurt). Whilst the hotel promotes the fact that windows open, our room tended to resemble a furnace most of the time, despite being provided with a rotating desk fan. Upon opening up the windows, we were greeted with the constant sound of both vehicles and people which was far from ideal. To compound matters, the mini bar fridge barely worked and didn't keep things cold.

One of the "bug bears" from our previous visit was that the hotel bar was only spasmodically opened and disappointingly, nothing has changed. We were given complimentary drink vouchers on our arrival and when attempting to utilise on a Saturday evening was told the bar would not be opening.

Notwithstanding the above comments, the hotel has some positive features in its favour by way of being located close to the main rail way station and offering good sized and clean rooms, along with the fact that a first class breakfast (comprising both a hot and cold selection) is generally included in the room rate. Furthermore, staff are pleasant and free internet use is available in the foyer or accessible via wifi from your room for a nominal cost.

In summary, the hotel is certainly not 4 stars as promoted but is more akin to 3 star hotel offering reasonable value for money. At the end of the day, if one was considering staying at this hotel in summer, it is probably a matter of weighing up the "pluses v's minuses", although I would certainly recommend requesting a room away from the main street to try and minimise noise, should the windows require to be open.