Originally Posted By: Alex
Also you may consider a couple of N95 or better dust masks,


I had one in my kit when I was commuting by rail; I don't any more. I'm going to reconsider that decision.

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pen sized high voltage detector (especially if you are in the city with a subway).


I don't think there's any way to safely test for train voltage with gear that isn't at least a yard long.

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paper city map


Agreed, especially in a city you don't know well. Keep in mind that most of the time you don't want to look like a tourist.