I want to see london at night. When's best time to go for evening walk?

Travelling two hours for no valid reason is in contravention of lockdown. 
The best time will be after the restrictions have been lifted. As for being dodgy at night, I have never found it to be, but then I have been complying with the law.

It's a pandemic. You shouldn't be travelling at all. 

Photographically speaking, that period of dusk where there’s still some light and colour in the sky and the lights go on.  This time of year around 8pm onwards until about 9.30pm.  It won’t be that dodgy.

EVERYWHERE in the UK gets 'dodgy' at night in the early 21st century. Even Inverness. But The Boltons, and other parts of London are just as posh as they always were.

I’d say leave home around 5 to get into London. Around 7. Now that the clocks have moved 1 hour forward it should be just about getting dark by then. 

Most of London does not get "dodgy" at night. In normal times, thousands of people are out on the streets. But if you have to travel 2 hours and be home by 11, you'd have to leave at 9. Note that very soon now, the sun won't be setting until after 9, so you won't see London at night when it's lit up. 

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