title: Plotting 3D bars on top of the map using R
body: <p>I've found a way to plot 3D bar chart (<a href="https://stackoverflow.com/questions/26794236/ggplot2-3d-bar-plot">ggplot2 3D Bar Plot</a>). Thank you @jbaums</p>
  
  <p>However, is there a way to change the bottom facet to a map? So I can clearly visualize, for example, the population density using bar chart on a map to show the differences between different parts?  Thank you in advance. <a href="https://i.stack.imgur.com/Wg4jl.png" rel="nofollow noreferrer">plotting 3D bars on top of the map</a></p>