Distance is 1 metre between island and other surfaces. Enough to open cupboard doors/dishwasher, but also enough that you can use both surfaces whilst cooking without having to move too far. I had the same in my last kitchen, worked well for me. Central island is 3m x 1m. I don't mind the length - it allows me to have dishwasher, double sink with waste disposal, under-counter chef's fridge and storage for appliances (blender etc) all to hand on the cooking side. Far side has a recess for 4 stools.
Q