Yesterday morning we awoke to find a pair of boots standing in our window. They looked every bit like the ones that Stalin left on the plinth in Budapest after his statue was pulled down (roadtripone, passim). Or could it be Nathaniel having locked himself out of the room down the corridor? None of the above. For on further examination, blue overalls were growing upwards out of these particular boots, and were accompanied by a tuneful whistling. Motel One had the decorators in, or rather out on the ledge, touching up the windowsills. I wondered whether to invite them in to watch the turquoise guppies with us. The more the merrier I say. But Jannie was not keen.

Our first culture stop after breakfast was the Berlin Museum for Contemporary Arts – a favourite of Nathaniel and Amy. This was always going to be a risky venture, since my appreciation of the more extreme fringes of modern expressionism has been a constant disappointment to my son. While Jannie has the admirable capacity and will to beam her way through any old artistic tosh, I sometimes find it hard to suppress the occasional embarrassing tut or the odd, whispered ‘I don’t believe it’ when confronted with an empty frame or a piece of string hanging from the ceiling. But I promised to be on my best behaviour as Nathaniel and Amy guided us round.

We started well. There was an excellent video of how dilapidated and destroyed parts of Tirana in Albania had been brought back to life by the wholesale painting of neighbourhood buildings in startlingly bright primary colours. Then all four of us joined hands, entered an enormous blacked-out room full of mist, illuminated only by pinpricks of light, and tried to find our way out. So far, so good. There was a room full of Warhol at his best; some grand Roy Liechtensteins; some marvellous Anselm Kiefer pieces; and Robert Rauschenberg’s evocative paintings in thick oils. No problems here: everyone was having a good time. I started to get a bit twitchy, though, when we looked at twelve completely white canvases by Chinese artist Qiu Shihua. [‘Qui’s paintings initially seem monochrome, even white’ says the brochure helpfully]. Jannie moved me on quickly as soon as she saw my mouth moving, but the next room was an equal minefield. You’ll like Joseph Beuys said my son. He has an interesting obsession with felt and cooking fat. Nathaniel didn’t prepare me, however, for the recording of Beuys cackling Ya Ya Ya Ya Ya Ya on a loop for hours on end. Before I could utter ‘he’s clearly as mad as a badger’ I was eased onwards into another room to find our old friend Cy Twombly (Blog, Days 42 and 43), having moved on from paintballing the Battle of Lepanto, to smudging his canvas with a small bottle of Snopake. ‘I had a Poussin period in my head’ he confided to a colleague at the time. More tellingly, the brochure noted: ‘Twombly’s compositions suggest a generous sense of emptiness’. Martin: That’ll be right. Jannie: How about some nice cheesecake in the cafeteria? Good plan.

Fortified, we headed off to the south west of the city by train for a more sombre encounter. Our destination was platform 17 of Grunewald Station, where between 1939 and 1945, thousands of Jews waited to be deported to the death camps in Riga, Auschwitz and Theresienstadt. The memorial is a simple and intensely moving one: a single railway track, in a far, silent corner of the station, partly sheltered by trees, with a line of engravings along the track noting every day that the trains left, their final destination and how many deportees they carried on each occasion, sometimes as many as 1000 or 1100 on a single day. Candles, flowers and small flags left by the track were evidence that the site is well visited and remembered, although it was eerily quiet when we were there.

Our final stop yesterday afternoon, thanks to Nathaniel and Amy Tours, was the DDR (the German abbreviation for GDR) museum, which gives an interactive and generally light-hearted insight into what life was like under communist rule in the GDR. This was a real treat. It ranges from the hilarious (the East German attempts to follow western fashion with the use of crimplene); to the bizarre (collective potty training for all nursery school children); to the racy (nudist holidays for all); to the sinister (189,000 citizens employed by the Stasi to spy on their compatriots). My favourite hands-on exhibit was a lever which made the hands of all the members of the GDR parliament shoot up every time they were asked whether they approved of the Government. Every PM should have one.

We said goodbye to Nathaniel and Amy this morning in the lobby of Motel One, as they had another day of fun planned in Berlin before their flight back to London, and we were off to Hamburg. Or we thought we were. When I turned over the ignition there was a cough and splutter and then nothing. Someone [Jannie: not me, and that only leaves….] had left the boot light on for three days. So the following two hours was spent negotiating the arrival of the recovery truck and a comic sign-language exchange with a very helpful mechanic who had us on our way with a tweak of his handheld battery charger. Needless to say we drove all the way to Hamburg without turning off the engine, for fear of running out of juice again. We’re hoping that the 280 km run will have teased the battery back to life. Otherwise we might be stuck in Hamburg for a while. Though, from a quick stroll round the attractive old part of the city in the warm sunshine this evening, there clearly could be much worse fates.