I work with the Hilton Mainz to get rooms for my company. We use both the Mainz city hotel this hotel was renovated already and is a very nice little hotel, some do not like the location, but it is right in the city center and you can walk out the doors and be in the actions. I really like the Mainz city, the rooms are very nice and modern. Some do like the river view and the Hilton Mainz is the place for that. I was given a tour of the hotel as the works are under way. The river side lobby is still a shell, they have ripped everything out, this includes the restaurant. The lobby will be the first thing done, then they will upgrade the rooms on the city side wing. Then they will move to upgrade the river side rooms, and replacing one of the two presidential suites to deluxe plus rooms.
They have photos of the way the new rooms will look, it looks like many of the new modern Hilton in Europe. The bathrooms will still have the tub, and will be the same size.

As of today you enter and check in on the city side wing, if you park you still park on the city side, take the lift to 2nd floor and walk over the sky bridge to the city wing. You can have a full Hilton Breakfast on the 2nd floor on the river side wing.

Once all this is done, there will be the following classes of rooms:
Hilton Guest Room
Hilton Deluxe
Hilton Deluxe plus (river view)
Hilton Jr. Suite
Hilton Presidential suite (down to 1)

They will not be adding a executive floor or lounge..


Just a side note both these Hilton treat Diamond guest very well.