This is not a hotel Tip. This is a sightseeing Tip, for the Budapest Hilton has some interesting tourist quirks. First, the restaurant and bar have great views of the Hungarian Parliament Building across the Danube River. So does the Fisherman's Bastion, which is next door to the Hilton. We visit the Budapest Hilton to see the Roman ruins. Most visitors to Fisherman's Bastion either start of end their visit to the top of the old city walls at the ends of the Fisherman's Bastion. Don't. Visit Mathius Church, then enter the Bastion at the church end, walk thru the Bastion, and continue walking along the top of the old city wall until the sidewalk ends in a L shaped corner of the exterior of the Hilton. There is a pit there, where you look down at some of the ruins of the ancient Roman city that once occupied Castle Hill. Then enter the Budapest Hilton thru the front door. When inside, turn left, go as far as you can, and there is a hall to your right. There are several windows along the corridor that offer views of more Roman ruins.
How many modern luxury hotels or otherwise can you name that have Roman ruins in the lobby? This is not the most impressive sight in Budapest, but it is the coolest.