Complex sentence: Humen is served by regular direct buses traveling south from Guangzhou, and one can continue south by bus to Shenzhen's Window of the World theme park, from which one can continue on to the Hong Kong border by bus or the Shenzhen Metro.
Split into simpler sentences: Humen is served by regular direct buses traveling south from Guangzhou. Routes continue south by bus to Shenzhen's Window of the World theme park, from which it is possible to continue on to the Hong Kong border by bus or the Shenzhen Metro.