There is no direct way to enter a radius, but there are workarounds: A) Select 'Add Circular Link' from the context menu of Links. The radius is shown in the status bar (it is not possible to enter the radius directly here). You can then delete any unnecessary intermediate points by dragging the end point of the Link to any intermediate point in order to create the desired arc. Alternatively, select 'Split route here' from the context menu. For neighbouring Lanes, e.g. 5 m wide, proceed as as follows: - Define a curved Link with 5 m Lane width. - Select 'Create opposite lane' with 1 Lane from the context menu. - If the new Link was created on the wrong side, select 'Invert direction'. - Proceed in the same way, this time starting from the last created Link, until you have created all the desired radii. B) Use a script to insert the intermediate points in a circle as a polygon on a Link or Connector.