A long downhill
Go west towards the timeshares (Ocean Queen) and keep going. Go over the moutain with the radio tower and down to the river. (Excellent liloing here. This is the river that Mission 1 and 2 cross). For an easy ride(or walk) go to the far side3 of the river and btake the track right up the river. Follow it as far as you want. Going uphill it will be a pain after a few kilometers but if you only want a short ride its nice.
Otherwise keep heading along the road untill it flatens out ina small village. There is a track (rock) here heading down fast. Follow this and keep going and you will eventually end up back at the bridge where you just crossed the river.
Note. After you get doen to the river (where the village is) you will probably have to carry bikes up a short hill. After that you can ride most of the way and it is fast, good single track all the way.