Described embodiments include a system that includes a display and a processor. The processor is configured to position an indicator, in response to a positioning input from a user, over a particular point on a three-dimensional electroanatomical map that is displayed on the display, and over which are displayed a plurality of markers that mark respective data points. The processor is further configured to expand a contour, subsequently, along a surface of the map, while a selecting input from the user is ongoing, such that all points on the contour remain equidistant, at an increasing geodesic distance with respect to the surface, from the particular point, and to display, on the display, one or more properties of each of the data points that is marked by a respective one of the markers that is inside the contour. Other embodiments are also described.