When I started the day, I realized that by making yesterday a do-over of the the day before, I had actually forgotten that I had different plans originally. I considered doing those things today, but I already had stuff moved into today's schedule so I'll have to do it some other time.
My first item on today's agenda was to head to Tokyo Station's Character Street to check out the Hololive Store. I heard there was station-only merchandise so I wanted to see what it looked like. (I could have just looked this up lol)
To start with, I was a little annoyed because I couldn't get a train directly to Tokyo Station, and would instead have ride to Otemachi and then walk around 10 minutes. Once I got to Otemachi, I got a little lost and realized that the exit I was looking for was actually directly inside Tokyo Station itself. Even better was that Exit B8b (crazy exit name, I know) lets you out right inside Tokyo Character street.
But actually, this got me thinking a bit, what's the farthest you can walk in Tokyo and stay inside stations? The walk from Otemachi to Tokyo Character street let me stay in the tunnels and was something like 800 meters.
I took a bunch of pics of Google Maps and stitched them together with panorama software to get a better picture of the Tokyo Station complex (let me know if anyone has better resources for this!).

As you can see, it looks like at least the following stations are interconnected: Tokyo, Otemachi, Nijubashimai, Hibiya, Ginza, Higashi-Ginza and Yurakucho. There are a few, like Ginza-itchome, that are super close.
My quick best guess for this station complex for the longest walk you could do is entering Otemachi at entrance C2b, walking though Nijubashimae, Hibiya, Ginza, and leaving Higashi-Ginza's exit 6. I don't know if this is actually feasible since sometimes some entrances and exits can be on opposite sides of the platform so you'd need to enter and exit the platform (IDK about fare etc.) if that makes sense. This also is the longest path I can think of that makes sense to actually travel, you could travel infinitely long if you just zig-zag through Tokyo Station or allow loops.

The total distance by using that route is ~2.6km (~1.6mi). Pretty far for staying inside a station. If I run out of plans, I'll try it sometime! I'll also research another time about the overall question of farthest you can walk in interconnected stations.
Back from our tangent, I made it to Tokyo Station Character steet and found the Hololive store. There were station-specific goods, but nothing in particular that I needed. I ended up just buying a few stickers. Also a little funny but I also ended up paying the ¥5 or whatever fee for a small bag and it ended up having the Hololive Tokyo Station official shop branding so I was thinking this is the cheapest way to get merch lol
Not pictured: station-specific merchandise lol
I looked around at a few of the other stores but I wasn't super interested in most of them. Things like Snoopy, Miffy, Chikawa, etc. are all super popular and take up a decent number of the shops. I did end up purchasing some more stickers (Apothecary Diaries, Frieren, Himiko Toga) and a Tenya Iida (from MHA) mechanical pencil as well.
After leaving the station, I headed towards the Imperial Palace area. My phone GPS had no idea where I was for like 15 minutes and I had to use my eyes to figure out how to navigate (the horror!). Once I finally made it to the edge of the imperial grounds, I saw a gate and almost decided to go in and check it out.

But then I realized, I've literally already been before! The gate leads to the Imperial Palace East Garden, which is pretty nice, but I felt like I didn't need to go again. I would like to see the Imperial Palace someday, but today is not that day!
I continued on my walk towards the National Museum of Modern Art, Tokyo. I actually didn't realize this until now, but this was fulfilling a checklist item from my 2023 trip (partially, I still didn't get to go to the science musuem)! The area around the Imperial Palace is pretty open so I felt that the sun was being even more oppressive than usual. I didn't want to sunburn so I even whipped out my umbrella for a bit.
You can tell it's a staged photo because I'm not wearing a mask
I actually hadn't know what was on display at the museum, but when I arrived I just got the ticket to see both the main galleries and the special exhibition. The current special exhibition was showcasing art from World War II, including Operation Record Paintings (offical art commissioned by the military), War Record Paintings (battle scenes etc. not commissioned by the military), and general wartime art.
The exhibit was pretty interesting overall and worked to talk about the art while explaining the context and how pieces were used as propaganda.
The greeting at the gallery entrance
I definitely learned a lot here and ended up spending way more time at the museum than expected, which is why I wasn't able to go to the Science Museum as well. There were definitely some striking pieces like the one below. It's also interesting to think about how during war the painting might be depicting heroes doing their part but the other side wouldn't see it that way, since this is depicting soldiers before they launch a surprise attack.
Commander Sano Bidding Farewell to the Ono Volunteer Corps, Konosuke Tamura
Towards the end of the exhibit, there was also art from non-artists that had been solicited in the 1970s (I think, I forgot to photograph the placard) from survivors of the atomic blasts. It was pretty touching and sad. I got teary-eyed looking at a drawing of a girl trying to give water to her dead mother in the aftermath. I think the exhibit did a good job of making people think and also teaching about the history of the era.
After seeing the special exhibit I was actually pretty tuckered out already but decided I should also take a look at the main exhibits since it was included in the ticket price. This exhibit consisted of 12 rooms, generally ordered chronologially, but the first room was titled 'Highlights' and included many of the museum's most highly-treasured pieces of art. The majority were from Japanese artists but there were also a few names I recognized from the West like Georgia O'Keefe or Henri Matisse.
The Highlights room also had a few really eye-catching pieces like Harada Naojiro's Kannon Riding a Dragon, which is also a National Important Cultural Property. My favorite piece of the entire exhibit was also in the Highlights room, Milky Way by Matazo Kayama. Unfortunately, it was one of the pieces for which photos weren't allowed, and there also don't seem to be any good quality pcitures of it online. This blog has was appears to be a scan of a book that has a photo of it? In person it's more striking and since it's comprised of folding screens, I feel like that also adds something to it.
Since I couldn't get a picture of that one, I'll leave you with a photo of the runner-up favorite, Stream in the Evening Glow by Toyosaku Saito. I think my phone camera is doing weird stuff to the photo but alas.
Stream in the Evening Glow, Toyosaku Saito
Wrapping up the rest of the day briefly because a bit tired of writing now (lol), I made my way to Jinbocho to see if there were really bookstores everywhere. And there really were, at least in the small slice I visited. Also seemed to be a lot of cafes and stationary stores as well. Actually, I had seen that one of the cafes was holding a gallery for an artist and the art looked good, but I actually got a little suspicious that it was AI after seeing the hands on one piece on Twitter so I didn't go. I will look up later and really go but didn't have enough information at the time to decide haha
After that I walked home. I actually ordered the places I visited decently reasonbly today to max out my steps. Basically every 1 or 2 km, I had something I wanted to visit, so I was able to push myself to walk everywhere instead of riding the train between places. Not only is this good for health, but you see sights along the way you would have missed otherwise! But I won't do it that way every day or my legs would kill me lol