Development of the external API is at an early stage. There will be several place and dataset endpoints with numerous filtering and search options, to: 1) the relational database, accessing records from contributed datasets, 2) the "union index" that gathers all place attestations (and related trace annotations) for a given place, and 3) a listing of contributed datasets.
Note that contributed records will have "permanent" URIs within the WHG system, allowing WHG to serve as a publisher of linked data for those projects unable to stand up per-record landing pages.
These are a few native Django REST API Framework screens available so far:
A contributed record (Verapaz): http://dev.whgazetteer.org/api/places/140167/
The "union" record for Istanbul: http://dev.whgazetteer.org/api/union?idx=whg02&_id=12345979
List of datasets: http://dev.whgazetteer.org/api/datasets/
A single dataset: http://dev.whgazetteer.org/api/dataset/1