I (Phil) was in London for almost two days for a conference: lowlight of the trip was arriving at my hotel in Knightsbridge at 23:00 to discover my hotel reservation had been canceled (and subsequently trying to find a place that wasn't £400/night). Highlight is tied between the cool stuff I learned at the conference and the Shake Shack cheese fries (didn't have time for a proper meal - I got there after dinner with colleagues about 10 min before closing). I forgot how huge London is: it took me 85 minutes to get from the East side to Heathrow in the tube; my flight to AMS is about 50 minutes.
Thames, etc. from the bike path.
Vegetarian dessert.
That's what the conference looked like.