Systems and methods are provided for obtaining a signature for a place. A server receives information about a place, such as name of the place, from client devices when the devices are at the place, and data related to wireless transmission stations detected by the client devices. The data comprises wireless transmission station identifiers and signal strength information. The server associates the information about the place with the data. Systems and methods are also provided for detecting a place for a client device. The server receives data related to one or more wireless transmission stations detected by the client device when the device is at the place. The data comprises wireless transmission station identifiers and signal strength information. The server compares the set of data with signatures of places, selects a signature based on the comparison, and transmits to the client device information about the place in the selected signature.