Hi John and Margaret,no one seems to care to be honest,and you'll probably be more of an attraction,as campervans have been quite rare in BG.
Now Bulgarians are seen with them,mostly hired though,you will see the odd,German,Italian,Polish,most are heading for either Greece via Serbia/Bulgaria or Turkey ,same as above or Italy/Greece coast to Turkey.There are some lovely quieter beaches to be found on the Black sea,as well as the 'kiss me quick' umbrella types like Sunny Beach and Golden Sands,loads of hustlebustle and tourists there,the quieter beaches are usually frequented by German,Russian or Bulgarian themselves,Sozopol being a small friendly 'middle of the road' fishing village/beach,where you can camp for free alongside the old harbour quayside,which is for visitors cars but i have stayed there many many times 5 days at a time,as long as your not blocking a view or resturaunt !
Another coast is the one from or near to Kavala on the Greek coast,if you have time,follow the smaller coast roads not the motorway or dual,as by doing so,you will find lovely places and villages,Nia Araklitsa is one with it's Lidl's and small fishing/yaught harbour.
I only live approx 2 hours away from Istanbul ,but have never been there !!! as its a huge busy city,not for the faint hearted in driving,i would imagine,but i've been to Erdine which is near one of the border crossings to Bulgaria and Svilengrad,there is a big market of all sorts on a Sunday there,also 3 beautiful Mosques that you should see,i was fascinated to find that the Celts,conquered and lived in this whole area around 200 B.C !!
There is an amasing amount of history and archilogical artifacts and places to see,in Bulgaria,Greece and Turkey which dates back more than 10,000 years,if you nip over into Turkey,you should visit the coast where TROY is,walk round the actual ruins and further down is a huge 8km sadly overgrowing now metropolis named after Alexander the Great,also Gallipoli and the Dardenelles,many free wildcamping sites if you follow the coast,amazing and no bother at all, i find that big tourist traps,cities or ports ,you might get the 'wrong type' roaming about but smaller places all know each other etc,so no crime,in Bulgria there are thousands of mounds from all sizes,most have not been opened as they are burial tombs,dating back 3000 yrs or more,they are usually in clumps of three and some as big a small mountains/hills,i have 3 in my village,undug,the other day there was a dig 50 miles away and a full size gold charriot found with many other ornaments and detailed gold artefacts,i would read up on Bulgaria and the Thracian kindom,if your into history,many Roman emporers were Bulgarian !so was the soldiers,Spartacus the most famous,they were renowned for their fighting skills and curved/bent swords.
Bulgaria has so many different scenery and wildlife,from high mountains with snow,to many rose filled valleys,great lakes and damns and long winding rivers,most are not used and deserted,wild animals still roam in the more dense and quieter spots like Bear,Wolf,Wild Boar and Dear,i have seen 3 out of 4,i dont really want to bump into the first.Bulgaria can be like stepping back in time 60 years or more,as in the country its very basic with donkey and cart,but with brand new modern 4 x 4 's passing
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shops are in every village and supermarkets mainly the German type in the cities/towns,LPG is at every garage and petrol is approx £5 a gallon/5ltrs..it was £3. Greece is more or less the same price as the UK and Turkey's fuel,i thought expensive at around £8 for 5 ltrs,there are many camp sites from basic to 4 star,but 'wildin' next to tthe beach or on the beach for free,makes up for it ! Google and internet Bulgaria and maybe Turkey,as Turkey does seem slightly different again more Eastern,Greece is Greece
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I would like to see more Motorhomes in these parts,as its so different to France and Spain,they seem so British....in comparison to BG and Turkey,again you cant really count the tourist traps as they are much the same where ever you go these days,like you said bars and umberellas.If your into history and culture,a different lifestyle to the norm,then try to head for BG and Turkey,its 2000 miles,a nice route is to Germany (nurenburg?) down into or through a Swizz pass from there and into Italy,all along the coast there to the ferry to Greece,theres three different ferries from different parts of Italy to Greece, or the different route of Germany Austria,Hungary SERBIA or Romania into Bulgaria,these are again different and beautiful,Serbia will cost you approx 120 Euro if you haven't a green card for that country,but a faster more direct route,than Romania,so swings and roundabouts really,and again Italy/Greece is in the EU,so more 'normal' .Plan well and you'll have a trip of a lifetime,no i'll take that back because you'll want to come again...
As i said before anyone is welcome to stay in my half acre,to refresh ,look around,leave van,empty,fill etc for a week or three or you can book into a nearby British campsite (30Miles) or the many others scattered about Bg.