Guangzhou is the first city in China that open to do business with foreigners in Qing Dynasty. I think there must be many historical things to see. I also recommended you Baiyun Mountain, which is a famous scenic area in Guangzhou. Beside this, Cantonese people are known for their cuisines, tour around Guangzhou for a day and have a taste of the local flavors is a good choice to visit here! Have a good trip!