HangZhou is a lovely spot in the south of China. I was deemed designated navigator (map always in hand!) and fell in love with guiding during this trip!
The best way to see the city is on bicycle - ride up the tea mountains and have a tea sampler in the museum. Then park the bikes for a stroll through the park, there are also some amazing restaurants all through the center (we went to Haveli - an Indian restaurant that was setting off fireworks for the Diwali festival!). The main street has a delightful lane of cafes and restaurants - we spent our evening in one such cafe with an amazing jazz band that serenaded us from an upstairs balcony. For any traveler hitting up the south-east, I recommend this route: HangZhou, ShangHai, SuZhou, and Nanjing.