cost of traveling from hong kong to beijing by train roundtrip??? For one day?

I want to visit beijing for like a day or two and am staying in hong kong....I was wondering how much it would cost for a round trip and if i should book it in advance??? All I want to do is visit the great wall of china and forbidden city......also attending an olympic basketball game during that time period......not sure how to find the price of round trip ticket.....i would find a hostel easy if needed though...... just curious about the train

Hard sleeper is HKD587 (the best deal, relatively comfy), soft sleeper is HKD934, deluxe soft sleeper is HKD119, bought at the ticket counter in Hong Kong. A bit more, but not by much, if you book in advance through www.chinatripadvisor.com

Roundtrip is double.

The station in Hong Kong is in Kowloon and called Hung Hom, also known as Jiulong. Fares and and schedules are found also on www.mtr.com.hk, select Customer Site then Intercity Passenger Services then More Information. Hong Kong is shown as Hung Hom.

Hostel in Beijing, check the Home Inn, usually a single is 169CNY, and a double is 199CNY.

a single trip cost aro US$140-150 by train. it's take 24 hrs to arv Beijing....kinda far. so u can't just spend 1-2 days to beijing. on the train u aldy need to spend 48hrs at least roundtrip. Beijing is really far fr HK....even thou u take flight. it's fly almost 4 hrs...... kinda like flying time of Japan. the train between HK & Beijing / Shanghai r run by.....

http://www.mtr.com.hk/eng/homepage/cust_index.html