An hour south of Mexico City is the city of Xochimilco. Xochimilco is unique due to Lake Xochimilco. This has created a gondola like atmosphere with a part twist.
Artificial islands called chinampas are located on the lake. colorful boats called trajineras to take you to and from the islands. A trajinera cost 500 pesos (USD 26) an hour which take you round trip up and down the river.
There are mariachi bands on boats too. The mariachi bands cost 180 pesos(USD 9.50) for a few minutes of music. It was definitely an experience. Sit back and watch everything come to you, from tacos to roasted corn and Micheladas.(Beer with lime juice, cayenne pepper, lime, and tomato juice.) One of the more interesting things I had was chocolate covered ants.
Not sure what was most impressive, seeing people push these huge boasts down the river or seeing how business is done in almost a floating market scenario.
There are gift shops and restaurants around the canal. They are in walking distance and will give you a unique experience too.