Which ship are you on? The bed height is different on the Wonder. The door width is 25.5" on all ships unless you have a handicapped accessible room then it is 32" Here is info on the Dream, the Fantasy and Magic should be comparable. https://www.flickr.com/photos/jenniferanddavemarx/5408368892/
On the Fantasy we measured the actual door width at 26.5 inches.
Now the door jamb and door eats up some of those centimeters as the door opens into the cabin.
We came up with a hair over 24 inches of available space with the door open.
Therefore we feel you have 24 inches of available space to enter cabin with the door fully open in a non HC cabin.
Ours did not fit under the bed on the Wonder but it did fit in the closet. It also fit folded up on the side of the verandah. Our room attendant said it was fine to leave it out there, but I have read that some have had different experiences.
I didn't measure, but the beds on the fantasy would easily go over an umbrella type stroller. They were tall enough for our large suitcases, but I didn't need to bring a stroller this winter, so I don't know about the larger strollers.
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