The Hilton Milwaukee City Center is a huge, historic hotel located adjacent to the Delta (Frontier) Airlines convention center (skyway connection), and about three blocks from the Amtrak station. Staff were friendly, and the rooms large, clean, and comfortable. The public areas, especially the lobby, are stunning and beautifully maintained. There is no pool, but a waterpark is open on weekends for an additional charge. The staff were friendly and helpful.
Hilton HHonors Gold/Diamond members receive free Wifi and access to a lounge with free breakfast and evening snacks, otherwise there is a charge. Parking is quite expensive, although the ramp is connected to the hotel by a skyway.
There isn't usually a whole lot going on in downtown Milwaukee, unless there is a convention. There are a few restaurants within walking distance and a virtually abandoned shopping center.
This is a big convention hotel, in my opinion, a step above most.