Our family of two adults with our 6 year old daughter stayed in Castello for a week in august and couldn't find a thing to complain.

Our superior room in Casa Marionette was quiet and cosy. Probably the A/C was a bit too noisy but it wasn't a problem as it worked well. The room had an individual entrance from the backside and from the other side we had exit to the beautiful garden and the pool.
We had no lake view but the view to flourishing trees and far mountains was remarkable.
The hotel territory looks like green and stylish tropical garden. We enjoyed every minute of staying.

Hotel staff is very friendly and helpful, making everything for the guests to feel them comfortable.

The hotel is not cheap, but I can recommend Castello to all Ascona guests for its unique charm and hospitality.

We stayed here over the May 1st holiday and paid CHF 348 for a night in a small dbl room with a side-seaview (sea could hardly be seen). The furnishings were shabby and outdated and the room was very small, although it was clean. And the toilettries are sub-standard or let's say nothing which a woman would want to use. Very annoying!

Another thing which was irritating was the street noise at 1am!! As the hotel is located at the beginning of the pedestrian zone next to a main street and a large parking lot, there were youngsters racing around in their cars and on mopeds with loud music and squeaking wheels. So I couldn't even get a peaceful night's sleep on top of it all.

I must say that for the high price, the hotel was very disappointing indeed. The one major plus point was that the receptionist on night duty was very friendly and helpful.

We stayed here for three nights and had a simply charming room with a large balcony overlooking the gardens. The bathroom was superb, the bed very comfortable with soft sumptious linen and the decor was more like a being at home then some grand hotel which felt nice. I think the room had recently been redone as everything was very new and tastefully decorated. The reception staff were very friendly and helpful and made you feel very welcome, with a smile and an acknowledgement if they were serving someone else. Simple things but so vital to the overall feel of a place. We loved Ascona (which can only be described as an "upmarket resort"). One tiny little complaint (which didn't really affect us) was that the sun beds around the pool were commondeered early in the morning and when I settled myself on one that didn't have a towel a rather disgruntled German lady came marching up to me as if I shouldn't be there. I couldn't understand what she was saying but I am sure it wasn't a form of welcome. You can also sunbath around the gardens which are charming and very quite. We ate in the restaurant on August 1st (the Swiss National day) and it was excellent. This is not a cheap hotel to stay in but one that we would deffinitely recommend if budget allowed.

We stayed at the Castello Seeschloss in mid June 2006. We were initially a little disappointed in the hotel and the town of Ascona. Ascona has a very busy, touristy pedestrian promenade along the lake, however, the views of the lake and surrounding hills from the promenade are lovely. The hotel is directly on the promenade with lots of pedestrian traffic. We were glad not to be staying in the most expensive "castle room" since it directly overlooked the promenade and one night a community talent show (teen models) was held directly in front of the castle tower with booming music and loudspeakers until midnight.
The interior public rooms of the hotel are beautiful with stunning stonework and tile floors, wrought iron etc.
Most of the rooms face an interior garden courtyard with beautiful tropical plantings and a small outdoor swimming pool. Many rooms also have small patios with a small table and two chairs.
Our room was also a disappointment initially since the furnishings were tired and in need of a replacement about a decade ago. In the US a room of this quality would go for much much less. The garden area outside of our room was so lovely and peaceful that after a day we got over our disappointment with the room.
I had phoned ahead to be sure our room would be airconditioned and was told that the expensive castle rooms had airconditioning that was "turned off at midnight" so we requested a quiet garden room and were assured the a/c functioned 24 hrs per day. Our a/c consisted of a motel type unit that was ineffective. The only time you could feel any cool air was if you positioned a chair inches from the a/c. Our friends had a room with a better a/c unit and their room was relatively cool but not up to US standards.
The heat and humidity level in Ascona were almost unbearable. The only relief we got was going up to higher elevations e.g. the Centovalle and another mtn valley. A boat ride was also very pleasant with good breezes and wonderful views.
Air conditioning is almost non existent in Switzerland- even restaurants, grocery stores and museums lack a/c. If you sat on a public bench in the shade directly in front of the lake you could catch some nice breezes. Thankfully at night it always cooled off and we slept with our windows and patio doors wide open (no screens but bugs were not a problem).
Mattress was typical Swiss extra firm (no box spring) but not uncomfortable and the linens were of high quality. The bathroom was nice and up to date. Maid service was excellent with nightly turn down service.
The front desk staff were exceptionally nice and accommodating.
The food at the restaurant was outstanding- both for breakfast and dinner. I recommend the half board plan. They also have an attractive lakeside cafe across the street/promenade with excellent food or lighter snacks.
Breakfast was extensive with a wonderful assortment of breads, fruit, cheese, soft boiled eggs etc etc. It was held in a covered patio area overlooking the gardens.
Most of the other guests were German and Swiss and appeared affluent- we encountered very few Americans in the Ticino.
Ascona overall was casual with very casual, summer dress (shorts, tank tops) acceptable everywhere although guests at our hotel dressed up a little for dinner (nice casual).
I would consider another visit to Ascona but only in the winter, spring or fall. I would also probably splurge on a higher quality hotel like the Eden Roc. If traveling in the summer again I might consider a less expensive, out of the way hotel up in the hills e.g. village of Intragna.