is it possible to walk underground from taipei main station to ximending?
i havent found a map and got lost on foot. the closest i could see is the national museum
Not possible. You have to surface around Beimen. You can walk underground in the opposite direction though, all the way to Shuanglian station.
Yes as noted there’s about a 1-2 block stretch between Beimen MRT Station and the underground passage on Zhonghua Road leading south to Ximen MRT Station.
There’s a lot of complex underground stuff in that short stretch including (I think): Taiwan Rail, Taiwan High Speed Rail, and the MRT Blue and Green Lines.
I wonder if that’s why they didn’t connect the dots here. It’s almost like we need a Han Cheung deep dive to answer this question!
Guy
Waiting for the first foreigner to be rescued from that maze after wandering for days 
After eating at all the places and drinking all he can drink alchhohol or otherwise
Do not overlook the knife massages, the maid cafes, and the Indonesian buffets available underground en route (well, at least partially to get to Beimen MRT Station—after that one does need to go above ground for a stretch to make this Journey to the West [Gate] work!).
Guy
Not much alcohol available down there.
Convenience stores or the connected Q-Square Mall.
no beer with all that food?
They are mostly Indo places down there. I don’t think Muslim operated buffets typically offer booze.
Guy
However there are certainly enough places to drink around there up in the light