If you are travelling with your spouse or siblings, this may not be a bad idea. A double room has one large double bed in it. The beds are generally pretty big and two people can fit in together quite easily. It is important that the person with whom you will be sharing the room is someone that you are comfortable with. Generally it works if two guys or two girls are sharing the room. Friends generally are okay with a double room as well. Otherwise you may be in for an uncomfortable night.
The rent for the room is much less than two single rooms so it is not a bad option if you are trying to save some money.
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It is something that most dorms offer and people are quite comfortable sharing these. The room has the same size as a double room but has two normal sized single beds in it. If you are travelling with someone that you are not too comfortable with, you can still share the room as the beds have a considerable distance between them.
The rent is much less than that of two separate single rooms and you can save some money while maintaining a reasonable amount of personal space.
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