Rain. It’s been an incessant feature of Autocar's trek in a Nissan Qashqai from its birthplace in Sunderland to Istanbul, where Europe meets Asia.

Yesterday was no exception; it had been raining when we arrived in Sofia, Bulgaria, on Saturday evening and it was still raining when we left the gloomy capital on Sunday morning.

We made a couple of quick stops in central Sofia to grab some photographs of the Qashqai at the city's sights, including the impressive Cathedral of Saint Alexander Nevski.

Then we were off, southbound across rural Bulgaria towards the Turkish border, putting more miles between us and our starting point in Sunderland. On the city limits of Sofia we were pulled over at a police checkpoint, despite travelling well within the speed limit.

The policeman asked to see my driving licence, then seemed to forget all about it when we told him we were on our way to Istanbul and waved us on our way. Snapper Stan Papior suspected he just wanted to look at a car with the steering wheel on the wrong side. 

We drove on across a flat plain in Bulgaria and passed through some fairly run-down-looking settlements, where villagers sat on deck chairs and touted food or souvenirs. I wondered how it was possible to tempt enough passing trade to scratch a living.

That quiet way of life was a sharp contrast to the insanity of the Bulgaria-Turkey border. Trucks, cars and buses queued, while pedestrians crossing the border on foot weaved in amongst them with their bulging wheeled suitcases.

Our border crossing took roughly an hour and a fair bit of toing and froing, due to slight paperwork mishaps and language-barrier issues. We had to present the correct documents and, crucially, have a barcode sticker applied to our passports.

However, our border wait was nothing in comparison to the truck drivers, who formed an orderly queue on either side of the division between the countries. Using the Qashqai’s trip computer, we measured a seven-mile queue to cross from Bulgaria into Turkey, and a 12-mile wait to bring their trailers of goods the other way.

Cars don't have to queue in the same lanes as trucks, but on the Bulgarian side the road is only two lanes wide, with lane one choked with trucks. What happened next was slightly unnerving – everyone in a car drove down the wrong side of the road to overtake the trucks. The cooperative HGV drivers left gaps between their queueing vehicles for car drivers to duck back into when oncoming traffic appeared.

We eventually got through the border and thought we'd left the madness behind us, but at the first toll booth on the ensuing motorway an alarm sounded and we were pulled to one side by the officials. 

Turns out we didn't have the windscreen vignette needed to travel on major roads in Turkey. No problem, the cheerful official told us, we could pick one up in Istanbul. Which seemed a trifle generous on his part, given that it was 140 miles away…

That last part of the trip to Istanbul took the Qashqai close to 3000 miles for the entire journey so far. After the relative calm of our drive during the rest of the day, entering Istanbul was a massive shock to the system. With Cool Hand Stan at the wheel, we managed to avoid any incidents, although even from the passenger seat I was mightily glad of the Qashqai's high-rise seating position and all-round decent visibility.

Today we plan to remain in Istanbul to tour around some of this amazing city's sights in the Nissan. It will be a welcome relief to stay in one place for a day, although the journey so far has been a fascinating immersion into different European cultures. Tomorrow, though, the return leg to the UK begins and that promises to be an adventure in itself.

It seems to have stopped raining too...

Follow our progress at @matt_burt_ and @autocar.

Nissan Qashqai from Sunderland to Istanbul, day one

Nissan Qashqai from Sunderland to Istanbul, day two

Nissan Qashqai from Sunderland to Istanbul, day three

Nissan Qashqai from Sunderland to Istanbul, day four

Nissan Qashqai from Sunderland to Istanbul, day five

Nissan Qashqai from Sunderland to Istanbul, day six