On 29 December 1696 Seaman Caspar Broel on board the Geelvinck, first sighted the Fog Island dead ahead, present-day Rottnest Island. Exploration of the Island, the Swan River and the coast to the north followed. After initial exploration of the island, Vlamingh went ashore and seeing numerous quokkas; and assuming they were large rats; named the island Rats’ nest or Rattennest. Due to high winds the expedition had not be able to explore the mainland properly and it wasn’t until 10 January 1697 that Vlamingh and his party ventured up the Swan River, naming it Zwaanenrivier after the large numbers of black swans they had seen.
The expedition set sail from the Netherlands on the 3 May 1696 in the Geelvinck, the Nijptangh and the Wezeltje under Valmingh’s command.
The crew of the Nijptangh, sailing under Vlamingh’s second in command, Gerritt Collaert, sighted the Great Southland (the West Coast of Australia) on Christmas Eve 1696. They did not see land again until the 29 December due to strong winds and currents. They finally sighted an island but with the onset of darkness it wasn’t until Sunday 30 December that de Vlamingh ordered the use of a boat from the Nijptangh, with Collaert and a small crew, to sail around the island in the hope of finding salvage of the ship they were seeking. The Geelvinck’s boat with the First Mate, the bookkeeper and 12 soldiers were sent to look over the island itself.
Towards evening both groups returned. The bookkeeper reported that there were no people on the island but that there were large numbers of bosch-rotten. They had shot a number of them to show de Vlamingh.  They were found to be dwarf kangaroos, a mammal still unknown in Europe at that time. In the journal of the Nijptangh they were described as a kind of rat, the size of a cat, with large quantities of its excreta being found all over the whole island. The island was named Rottenest.
From the holes that were dug on the island the men obtained good drinking water and of interest to the Company, they thought, would be the wood from trees on the island which had an exquisite smell – like rosewood. The following day de Vlamingh himself went on land and he was very impressed with the smell of the wood. He ordered a large quantity to be cut and brought on board. He commented in his log… found there the finest wood in the world, from which the whole land was filled with a fine pleasant smell. Meantime they saw the mainland, which stretched as far as the eye could see. He noted that there were many palls of smoke and on 3 January 1697 everything was made ready to investigate this. In the first instance a boat was sent to the mainland but because of the distance it was only able to carry out a short investigation. As a result a counsel was held and it was decided to mount a full expedition.
Eighty six men and the ‘native interpreters’ who had been taken aboard at the Cape, would make the journey. Captain Collaert was in command. On 5 January, 1697, at sunrise, the expedition left in Wezeltje and the boats. The expedition would take nearly four days.
On the first day, Collaert and all his men went inland. Near some small salty lakes they found human footprints, a small hut and more tracks of both adults and children, but the natives were nowhere to be seen.
Collaert thought that the natives may have been frightened off by the large expedition group, so he decided to split the group into three – but to no avail. On the third day, Collaert split the group again in two. Gerritt was sent with half of the expedition party to find the mouth of the Swan while he proceeded to meet them overland from the coast, landing near the Vlamingh Memorial site at South Cottesloe. In the meantime the aforementioned party arrived at the mouth of the river, sailing up it for some distance. It yielded little more than a couple of black swans which had never been seen before, two of which they took to show de Vlamingh.
Willem de Vlamingh decided to go and have a look for himself. On 10 January 1697 he left with three boats to explore the Zwaanenrivier (Swan River). The group travelled some 12 miles up the river until shallow water stopped their progress. They made no contact with the natives and all they had to show for their trip were two black swans and some resin and gum from the trees.
De Vlamingh had to concede that the land had little to offer and that the native population did not want to show themselves.
Back on the ships, the council decided to continue the journey northwards and life on board returned to its routine. Keeping close to the coast, when the weather allowed, a number of landings were made and the coastline carefully recorded. No humans were sighted and the land was described as dry dunes and unsuitable for cattle and people.
