You stayed at a youth hostel which was dirty and unsafe написать письмо жалобу по этой теме,

Some hostels are part of bigger networks, like HI (Hostel International), which regulate facilities and demand a certain level of quality and transparency. For more independent locations, Yelp and Tripadvisor are your best friends. That being said, take everything with a grain of salt. Lots of people book hostels online or over the phone with unrealistic expectations of both the facilities and their roommates. Don’t cancel your trip for one bad review, but mine as much information as you can. The goal is to know exactly what you’re getting and what you’re not. Breakfast? Wifi? Hairdryers? Some modern hostels offer luxurious amenities like built-in bedside reading lights, blackout drapes and air conditioning, but if they don’t flaunt it on their website, don’t expect it. After all, hostels are meant to be bare bone bargains.