Berlin, Berlin: we're going to Berlin! The famous German chant that rings around the country's football stadiums in the final stages of the German Cup, doesn't just apply to fans of the world's most popular sport. For 40,000 runners from around the globe it's fair to say that Sunday, 28 September is the most important in their sporting calendar. They are part of a select group of people who managed to get a starting position in this year's legendary Berlin Marathon, and I'm one of them.

The race's popularity continues to increase. This year, the number of applicants was so high that names were randomly selected by a computer. Up until last year, the first race came online as applicants logged in, frantically hoping to secure a spot on the start line. After those places sold out inside of a few seconds last year, organizers decided to make things a bit fairer this time round.

I didn't have to worry though. As a member of the "Jubilee Club" I have a start number reserved for life: 3176. I've been working towards this since 2003. You need to have finished the race 10 times in order to apply for a position at the "Jubilee Club," and you need to have the paperwork to prove it. My best time was back in 2004, when I finished in three hours, 24 minutes and 38 seconds.

"Flat, fast and unforgettable"

For some reason, the winners tend to cross the finish line near the Brandenburg Gate a lot earlier than I do each year. I don't know whether that's due to my failings or due to their dominance - probably a bit of both. And the winners are getting faster too. Last year the Kenyan runner Wilson Kipsang managed a marathon world record when he completed the Berlin course in just two hours, three minutes and 23 seconds. He continued the tradition of his countrymen Paul Tergat and Patrick Makau who also grabbed new world record times in Berlin back in 2003 and 2011 respectively. Ethiopian Haile Gebrselassie managed four race wins between 2006 and 2009, to keep the Kenyans at bay. His time in 2008 was also a record, for a while at least.

"Flat, fast and unforgettable" have been used more than once to describe the Berlin marathon course. There's no doubting that it is the fastest marathon stretch in the world. Of course this year I'm also dreaming of a new personal best, but it's unlikely that it will happen this coming Sunday. The first half of the year was a write-off for me. One injury after another, and I stopped training for a full six weeks at one stage. Now, thankfully, I'm feeling fit and have managed to prepare well. Since the start of July I have been on 40 long runs, some of them over 30 kilometers (18.64 miles) in length. I'm ready.

Why do I do it?

On Sunday, I will have to complete the full 42.195 kilometers though of course. The marathon tradition is now over 2,500 years old. There are many stories about how marathon racing first started. It's said that in 490 BC a messenger once ran from the Greek town of Marathon to Athens. Upon announcing the good news of the Greeks' victory in battle against the Persians, the messenger apparently collapsed and died of exhaustion. It's a tragic story, but also highly controversial amongst historians.

These days, in the 21st century, us runners, wheelchair racers and handcyclists don't really care much about the origins of the marathon. What brings us together is our passion, perhaps you could call it obsession, of challenging ourselves.

As an entrant in this year's race, I have to pay 98 euros ($124.77) to take part, and a lot of people think I'm pretty weird for doing it. They can go ahead and think what they want. This experience is worth the money every time.

One million people come out to watch us on the course and there are TV cameras everywhere. These pictures are beamed around the world, and they stay with me in my mind for months afterwards. They accompany me on my training days. Experiencing my own city, full of runners, is contagious - in a good way.

Just after we begin, the runners always cheer on their way towards Berlin's Victory Column (known in German as the Siegessäule), the famous landmark with the golden lady on top which commemorates the Franco-Prussian war in 1870 and 1871. Whenever I see the "Goldelse," as we call it here, I always think of my inner drive, because I really have to summon it for this race.

Every time I run the Berlin Marathon, no matter how much I prepare, it's always hard work yet somehow beautiful at the same time.

DW reporter Marcel Fürstenau has been running marathons since 2002 and managed his best time in Hamburg in 2013 clocking three hours, 23 minutes and 41 seconds. The 52-year-old will also be writing a post-race report next Monday (29.09.2014)