Some nice people in Italy have blended various oils ( particularly from the Amaryllis and the Euphorbia families of plants) to create a harmless gel that moles really hate.
The smell, which I doubt you will notice, gets them moles packing their bags right away, desperate get out of your garden. (On considering, perhaps you'd better not tell the neighbours what you are doing !)
If you are unlucky enough to have a mole already put around 10 cubes of inside it's tunnels ( yep, lots of 'hills' but probably you have only one mole.)
To keep them away, regularly sprinkle about 5 cubes of product for every square yard.
(The effects should last at least two weeks, but Moley would have got the message !)
Mole Repellent - 500 ml Gel Cubes