Beijing to Xi'An
 

I am leaving for a work trip to Beijing soon and I want to see the Terra Cotta Warriors. I know it will probably be a day trip, but I can't go all the way to Beijing without seeing them. Any suggestions for how to make this a one day trip? Train? Please let me know. Thanks!

Day trip by train is out of the question....I believe the train journey is over 10 hours. Flying will be the only way and even then, it will be a very long day.
I think you are pushing it to make this a day trip.

Technically, the OP can ride an overnight train down and then overnight train back up to Beijing. If that qualifies as a daytrip...

My friend was in a similar situation last month like you and did a daytrip by plane, she felt it was every bit worth it for the very long day.

Best of both worlds. Split it, overnight train down, so you get an early start without the bus tour crowds. Then fly back that early evening.