St. Petersburg has few alternatives in the budget travel area, so even though this hostel isn't very nice, it is ok especially in a city where you won't be spending (hopefully) much time in the hostel.
Located about a 15-20 minute walk from the nearest metro station, All Seasons Hostel is in the middle of an old soviet apartment building. Although there has obviously been some work done, there is still a lot of room for improvement. For instance, the beds are hard as wood planks even with three of the small, old, smelly mattresses under you. There's also no air/conditioning or screens on the windows which can lead to sleepless nights in the summer where you are forced to choose between the heat and the mosquitos.
The "common room" is actually a very small place with a little stove and a TV which honestly isn't very inviting. The bathrooms are clean enough and there's hot water. The staff are fairly friendly and speak English well. Also no internet although is as advertised, there were some computers in various states of direpair laying around so maybe someday there will be.
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Our children were bitten by fleas or bugs in their beds. The toilets were in such a state that we decided to buy a night pot for our two kids (aged four and two). The hostel announces a possibility to use internet services. It was out of order for ten days, and when we asked, the hostess told it was for a long time! They calculate the change roubles/euros on the bas of 37 roubles for 1 euro, when the normal rate is 33.5! Multiply the difference by the numbers of travellers ans the numbers of nights, and you will have an idea of the racket this consists of! The kitchen has never been cleaned, as long as we stayed. The rooms neither. No help from the staff, even when they saw us with two kids, two rucksacks, a suitcase, and a push chair. We went last summer in this bloody hotel, we won't do it again! 
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