And this man in the photo must was probably the same, looking at the mailbox so closely...
This is not a usual mailbox. As long as I know, this is the only "train shaped mailbox" in Tokyo.
What surprised me was that so many people actually posted letters into this mailbox in just a few minutes while I was taking this photo.
Sending letters and packages is something I am not good at. I wanted to send some postcards to overseas, but I haven't found a nice postcard of Japan yet.
Maybe it's faster if I order postcards from Internet using the photos I took myself?
PS I am not the only one who is getting worse and worse at sending letters, I hope.