These can sprout up anywhere in built up areas. You often won’t see them until you’re on top of one and quite often, there will be someone waiting in one, for a safe opportunity to cross the road.
Be Seen! Don’t ride too close to the kerb. People crossing from the island won’t be able to see you. All they will see is a gap, and they are likely to dash out in front of you.
Centre islands have raised kerbs. Some have bollards and/or signs at either end, to aid visibility. Read the road ahead before you overtake a slower vehicle, to avoid ploughing into the kerb or a bollard.
If the driver of a vehicle in front of you swerves unexpectedly, it may mean there is a centre island up ahead. Maintain a safe distance behind other vehicles in built up areas to avoid having your road space constricted by a swerving driver.

ROUNDABOUTS

Some roundabouts provide positive camber; a ‘lip’ on the road surface as you exit. Riding over this lip while the machine is banked over can compromise the performance of your tyres and turn it into negative camber where you can lose traction. Some roundabouts are higher in the centre than at the outside, providing a negative camber, to enable dirt or oil to stream to the outside, while
slowing traffic down. So, especially in the wet, try to keep to the inside of those roundabouts, and be prepared to lean further in than you may at first think, to get round safely.

Oil and fuel spills are common at roundabouts. Watch out for oil and fuel on the road as you head round, particularly in wet conditions and don’t ever trust an oncoming vehicle to give you the right of way. Take note of the road signs on your approach to a roundabout and be clear about where and how you need to exit. Think ahead and use the appropriate lane. Once on the roundabout, keep a reasonable and consistent speed if possible in order not to confuse other motorists. Use your indicators to let them know what your intentions are so that they don’t make assumptions and act in ways that can compromise safety.

Don’t assume that others indicating on a roundabout know what they are doing.
Watch the car in front. Rear-enders are common at roundabouts. Make sure the vehicle in front of you has pulled away before you start to move.
Keep an eye on the vehicles about to enter the roundabout, and those who are straddling lanes once they are in there.
Be aware that long vehicles need to use several lanes to manouver. Watch for their signals and give them plenty of space.
Stay behind cyclists until you know which exit they are taking or until you can pass them without threat of cutting them off as you exit.