  We propose a new task of recommending touristic locations based on a user's
visiting history in a geographically remote region. This can be used to plan a
touristic visit to a new city or country, or by travel agencies to provide
personalised travel deals.
  A set of geotags is used to compute a location similarity model between two
different regions. The similarity between two landmarks is derived from the
number of users that have visited both places, using a Gaussian density
estimation of the co-occurrence space of location visits to cluster related
geotags. The standard deviation of the kernel can be used as a scale parameter
that determines the size of the recommended landmarks.
  A personalised recommendation based on the location similarity model is
evaluated on city and country scale and is able to outperform a location
ranking based on popularity. Especially when a tourist filter based on visit
duration is enforced, the prediction can be accurately adapted to the
preference of the user. An extensive evaluation based on manual annotations
shows that more strict ranking methods like cosine similarity and a proposed
RankDiff algorithm provide more serendipitous recommendations and are able to
link similar locations on opposite sides of the world.
