When experiencing or describing a new place people will often compare it against other places that they already know. However, this human attention to the simultaneous similarities and differences between places is not reflected in the design of user interfaces of current place search technologies. In this demo, we present Frankenplace, an application for doing similarity-based place search that allows users to interactively find new places based on mixtures of features drawn from different places. The features of places are derived from a combination of authoritative data sources and unstructured observation data from social media, and organized into an extensible set of layers. We demonstrate the Frankenplace interface, which lets a user build a profile of a target place by selecting the most relevant of the properties shared by known places.