Bulgaria
We crossed the border between Serbia and Bulgaria after Pirot, this is the main road to Sophia. Crossing was fast, nobody really looked at us. We stopped just after the border to buy a vinieta, but a good thing - you do not need it for motorbike. First we drove across hilly landscape with extensive yellow fields full of sunflowers, but approaching Sophia the landscape got more boring and dirty.
Already befor Sophia we turned south to Dupnitza, from where we continued east to Sapareva banya. We found a small nice camp in Sapareva banya (6 eur per night for tent and 2 persons). We stayed for 2 nights, wanted to do some hiking in Rila mountains at first, but the weather wasn't too good, so instead we indulged bathing in thermal pool in a hotel in a centre of Sap.b. (very cheap, 5 eur for both of us).
From Sapareva banya we drove over Samokov, Kostenets, Belovo and Velingrad to Batak. There was suppose to be a nice lake and we had a waypoint in GPS from Hubb, but finally we didn't find any camping site there and it was very dirty, full of litter all around the lake, so we think it is not actually worth seeing. The place is overbuilt with dozens of villas and expensive hotels, but nobody cares for nature, so were not sure what they want to offer to tourists or travellers.
From Batak we continued south over very nice mountainous region of Rhodopes and at Dospat we turned east, heading over Borino and Devin to Smolyan. The countryside was very nice, wild and unspoilt, with mountains and lakes and some nice villages. We were travelling slow, observing nature and taking photos. About 20 30 km before Smolyan rain caught us and we arrived to Smolyan late in the evening soaked and hungry. We found a nice home-like hotel in the centre, Ralitza, There is no sign for it on the road, so its the best to ask (we were given the direction by a helpful worker at petrol station). Owner is a very nice lady who knew some English and told us for some nice walking paths, which we did next day. You can do some nice hiking in Smolyan, although it is mostly skiing tourism there, so it might be nice to visit it in winter. We went to see the valley of waterfalls, which is quite beautiful and worth seeing if you have 1 or 2 days time.
A winding road took us through last mountainous part of Rhodopes in the direction Haskovo. After Kardzalevo we turned to side road and travelled slowly through beautiful hilly landscape. Finally the hills were left behind as we reached Haskovo; only vast plain surrounded us. Without stopping we continued. Some 30 km before Svilengrad we stopped overnight in Sakar hills camping in small village of Biser (very nice and cheap camp, about 8 eur for 2 persons with a tent).
We found Bulgarian people shy and not very conversational. Only few can speak some English, so it is not easy to communicate and beside, everything is written in ciril alphabet, except for the signs on the main roads. If you ask for camping site, nobody knows, even if its 100 m ahead, so you cant really rely on peoples help. The landscape is very beautiful (at least the south, we dont know for the rest) and still very wild and unspoilt, just it is a pity that the nature is often very dirty; it seems people dont really care for the beauty they have.