A Wireless Sensor Network (WSN) is a key data provider for the Internet of Things (IoT). A WSN can serve as a tool for both identification and data generation. However, due to its inherent resource limitation the WSNs cannot generate and transmit large data streams and, therefore, typically transmit raw and simple sensor values. Furthermore, the sensors usually transmit their data in proprietary formats to an embedded application. This can be enough for WSN control and monitoring applications, but is not enough for the IoT where it is expected that thousands of different objects belonging to different context will be accessed remotely. In this work we propose to create a virtual representation of real objects (sensors) with a corresponding Virtual Object (VO) model. This VO produces not solely a stream of raw sensor measurements, but enriches those with context information. We evaluate our approach using a real city-scale traffic monitoring sensor network deployed in the city of Enschede, the Netherlands.