Read the example sentence.

Since the taxis and buses were out of service, the tourist town decided to begin using rickshaws, which were inexpensive, relied primarily on physical strength, and led to a new source of employment.

Based on the context, what is the meaning of rickshaws?

buildings that serve as train depots
underground transportation systems similar to a subway
small vehicles pulled by one person on foot or on a bicycle
carpool services for large groups