I live in Melbourne and cycle this regularly. Olinda is a small town at the top of the Dandenong Ranges. There are several climbs up to Olinda which vary between 6-7km and 4-6%. They are quite easy, but offer lots of variation and nice scenery. They are also only a 45 min ride from Melbourne, making them the most local climbs to the city. The most popular climbs is called 1/20 (so called because it is 4%...1 meter rise for every 20 meters travelled), The Wall and Montrose-Kalorama. See www.cycle2max.com for details and times of these climbs.