This example calculates an isoline in the reverse direction. The result is the answer to this question: From where can I get to the destination within a given range. This can be useful to determine which vehicles from a fleet of vehicles (Taxi service) can get to the destination within a given time, for example. To trigger calculation in reverse direction, use the destination parameter instead of start. 

https://isoline.route.ls.hereapi.com/routing/7.2/calculateisoline.json
?apiKey={YOUR_API_KEY}
&mode=fastest;car;traffic:disabled
&rangetype=time
&destination=geo!52.51578,13.37749
&range=600
Note: This example uses a HERE API Key to authenticate your request. For the available authentication options, see the Identity & Access Management Developer Guide.
Figure 1. Example reverse direction isoline representing a travel time of 10 minutes to the center of Berlin.