Few cities in Europe have a green space at its heart as vast, wild and endlessly surprising as Berlin. The Tiergarten, which began life as a private hunting reserve for the Electors of Brandenburg, forms a huge and tranquil green lung in the centre of the city, connecting East and West Berlin and running from the Spree to the Landwehr Canal.
The Tiergarten contains many of Berlin's most high-profile sights and it's inevitable that you'll enter it at some point during your trip to Berlin, perhaps without even realising.
Far bigger than London's Hyde Park it might be, but Tiergarten nevertheless breaks down nicely into manageable chunks to explore - and this is my guide to the most interesting nooks and crannies of the place. As with anywhere in cycle-friendly Berlin, the best way to explore Tiergarten is by bike, however you can also do so on foot if you're not easily exhausted.
The Reichstag, on the Tiergarten's far eastern end, is the obvious place to start. So obvious, in fact, that you should give it a miss and dive into the park directly to the building's south. Here are two obligatorily bleak but interesting monuments that many people miss: the Memorial to the Sinti and Roma victims of National Socialism, a tranquil garden surrounding a shallow pond, and, a little further down past the Brandenburg Gate, the Memorial to the Homosexuals Persecuted under the National Socialist Regime. Look inside the small window of the sloping cube structure to see a short film of a same-sex couple kissing.
From here, head into the park and follow the broad and not-so-broad walkways through the charming woodland to the busy Hofjägerallee road, cross it and return to the woods and here you'll find the so-called Tuntenwiese, or 'faggots meadow' to give it its literal, if politically incorrect translation.
This historic slice of the Tiergarten has been a popular nudist and gay meeting place since the 19th century, and remains somewhere that Berliners of all descriptions come to sunbathe nude. It's perfectly friendly, and despite the odd group of tourists being led on guided tours to 'see the naked people' that occasionally blight the view, it feels as perfectly organic to Berlin as it is (nakedness being something of a Prussian cultural norm).
The heart of the Tiergarten, conveniently forming the centrepiece to a huge traffic roundabout, is the Siegessäule, or Victory Column. It was actually first erected outside the Reichstag as a monument to the Prussian victory over the Danes in 1864, but was moved to its present location by Hitler in 1939, as he reorganised the city in preparation for the creation of Germania, the city he planned to the capital of his worldwide empire. Nobody seems to hold this little detail against one of the city's most beloved monuments, however, even if the French did at one point plan to dynamite it after the war. You can climb the column for a fabulous view of the park and the city beyond.
Just to the north west of the Siegessäule is perhaps the loveliest part of the entire park, the English Garden. With its neat flowerbeds, grass cut with military precision and topiary to rival any English stately home, this little-known corner of the Tiergarten is quite unlike elsewhere in the otherwise wild and naturalistic park. There's even a gorgeous little teahouse here for a spot of high tea and a scone to complete your cultural dislocation.
From here, continue to the Hansaviertel, on the northwestern edge of the park, which is simply an architecture student's dream. Having been totally razed to the ground in WWII, this neat little district was rebuilt in the late 1950s and early 1960s as a housing estate with modernist contributions from the likes of Oscar Niemeyer, Le Corbusier and Alvar Aalto. The whole area is now a protected historic site, and it's great to walk around its quiet streets and enjoy its utopian feel.
One popular sight in the park that shouldn't be overlooked is the superb Berlin Zoo. One of the most popular in the world, it is the birthplace of global celebrities such as Knut, the polar bear who was raised by his keeper after being rejected by his own mother at birth, and whose sudden death in 2011 is still a source of sadness for Berliners. The zoo was also where Franz Kafka discovered vegetarianism, while staring at the fish in the aquarium and resolving never to eat them again. It's well worth the entrance fee to see the big cats, the apes and the elephants.
End your walk or ride in true German style at the Schleusenkrug (Lock Tankard), an old-school Berlin beer garden by one of the locks on the Landwehrkanal, which runs along the Tiergarten's southern edge. From here, it's just a short stroll over the bridge back into West Berlin's traffic clogged heart, but until you leave, you'll find the city feels little more than a notion as you knock back your Hefeweizen to the twilight sounds of the animals in the zoo.