I visited Plovdiv because I knew nothing about it, and it was half way between Istanbul & Sofia. Arrived Plovdiv train station mid morning, no map, no info, no hostel booking. Although the buildings and people looked slightly more western than Istanbul, it felt more alien than Turkey.
I had the feeling I was in one of those movies where you wake up in a parallel universe where things are familiar but totally unintelligible at the same time - people nod for "no", do not speak any English and all signs were in cyrillic.There was no tourist information point, I walked towards the centre (the first passerby understood "centrum?"). The centre was half an hour walk, but after another hour of lugging my one ton back-pack and day bag around I still had not found any cheap looking accommodation so I booked into a hote for 35 euro. Of course as soon as I'd done this and gone for a walk I found a hostel. Plovdiv is not Istanbul its more the tourist equivalent of Reading or Slough. There is a Roman Amphitheatre sunken in the main shopping centre, some old churches and baroque houses.
Not being a tourist hot-spot there are few English speakers, the first person who was semi-inteligible spoke in French. That said those who did speak English e.g. a student I met in a cafe were very friendly and helpful, volunteering advice, taking time to walk with me and point out supermarkets and the best cheap eating places.
The following night I stayed in Plovdiv Inn Hostel. It was basic but clean, there were 8 beds in my dorm and there were 2 other dorms, it was like the Marie Celeste - I was the only resident. This is one town where, I must admit, I could have done with the company of fellow travellers. At both Hotel and Hostel despite those pluggy in ant-Mosi thingys I still heard the odd mosquito and added to my collection of bites. To be fair to Plovdiv it seemed to have a vibrant night life - while I was there laser show and music in the squares.
For rude comments on Sofia Train Station see Great Train Journeys.
Again I hadn't booked a hostel, and went to ring Mostel Hostel (which had good reviews) from the station. A Brit and Ukrainian asked me if I knew how to use the phone. By coincidence they were having difficulty ringing the same hostel which they had booked and wanted to contact for a pick-up from the station. The hostel had no room, but kindly gave me a (free) lift to town and took me to the nearby Sophia Hostel.
The Sophia Hostel was fine, but I moved to Mostel Hostel the following 2 day. Mostel deserves its reputation - to date it is one of the two best hostels I have stayed in. Friendly, helpful staff, excellent advice , and plenty of free facilities including internet (soon WIFI), free evening lager and spaghetti which get the backpackers mixing etc. The first night I went out in a group of 12 to the bars in the evening, unfortunately all blokes so we looked like an English stag party (the 2nd night one girl came out as well).
In view of the people at Mostel I would like to be able to say Sophia is a great city to visit - but I can't. The consensus of back-packers was you can see Sites of Sophia in an hour! I have to agree, they are all located on one road (churches, museums, art galleries)and none are particularly memorable. The hostel provided a map - with street names printed in the Roman alphabet - however the street signs used the cyrillic - so it was essential to learn cyrillic to know where you were. I actually found this good fun as once you know the alphabet you can get by and words sound exactly as they are spelt.The positives I take from Bulgaria are the cheap food (50 pence for 2 kebabs or 2 large pieces of Piza),the stay at Mostel Hostel, and the fun of working out what words in cyrilic say.
Bulgarians consider themselves to be poor. I did see gypsies checking rubbish bins for anything of value, including a one-armed gypsy with 10 year old daughter going from bin to bin with a hand trolley.
Certain parts of the two cities I visited needed repairs to the blockwork streets but development was also evident. Street cleaning appeared to be carried out my old women usinf witches brooms (ditto Romania) and I saw them empty the street bins by hand as they had no liners. Sofia - lots of dog pooh.