I agree the IC at the O2 especially given the London City departure. I’d suggest doing a tour bus (hop on hop off city tour, possibly just staying on to complete a full circuit).

Fish and chips in London, I would honestly ask a local. If you want authentic. It’s likely to be takeaway wrapped in paper / newspaper with salt & vinegar and ‘mushy peas’!

If you find a large queue to check in at the IC O2, PLEASE walk to the desk on the left hand side of the front desk, opposite - this will do you an Ambassador check in and is the ‘fast track’.

Look out (left) for bicycles cutting on the inside of taxis and buses when getting off or on.

In most restaurants in the UK, there is no need to wear a suit. I would say the UK is a pretty diverse / inclusive society especially in London and there is a wide ‘margin of appreciation’ when it comes to dress style, but if going to somewhere nice / expensive then I’d say, basically, no sportswear really. Some places, ie ‘classics’ can be dressy and if in doubt no trainers or shorts, otherwise pretty much anything goes.

I hope you are staying at the IC in Berlin - it’s one of my favourites.

oh and a plug for London Taxis/‘black cabs’ (I think their official title is still “Hackney Carriages” for licensing purposes) - they can use most bus lanes and their drivers do a test called ‘the Knowledge’ - ask a cab driver about it) - I think (a) it’s a London experience and (b) I still think they are the quickest around central London when compared to Uber.

PPS the fastest way to IC at O2 is almost always going to be by public transport especially if a river crossing is needed. New infrastructure is coming but the ‘Blackwall Tunnel’ for vehicles can get really really congested. Download the TfL App (TfL = Transport for London).

ppps - most museums are free. I highly recommend trying to go to see Tate Modern’s free exhibitions - you can walk to it down the bank of the River Thames and it is at a place called Bankside which is quite a cool area.