Royal Botanic Garden, Sydney

Listen for a moment. Under the cry of the gulls there is a softer sound: water lapping against a long sandstone sea wall, and wind moving through palm fronds overhead. The grass is cool and springy underfoot. The air smells of cut lawn, salt and eucalyptus. To one side, the white sails of the Opera House catch the light. To the other, the towers of the city rise behind a curtain of old trees. You are standing in a garden older than the nation it sits in.

Before any garden, this was Gadigal country. The Gadigal people are one of the clans of the wider Eora nation, and the shoreline of this cove was a place for fishing, gathering and living for thousands of years. The mudflats and rocks gave shellfish. The bush gave fruit, fibre and medicine. Today the garden openly recognises this history, and you will find plantings and signs that tell that older story alongside the colonial one.

The colonial story begins in 1788, when the First Fleet arrived from Britain. Almost immediately, the newcomers cleared ground here at the edge of the harbour to plant crops. This became the first farm of the colony, and it gave this bay its name — Farm Cove. The early harvests were poor. The soil was thin and sandy, and the settlers did not understand the climate. For a while the colony came close to starvation. So this ground holds a quiet record of struggle as well as growth.

In 1816, Governor Lachlan Macquarie formally established a botanic garden on this site. That makes it the oldest scientific institution in Australia — a fact many visitors walk past without knowing. Its early purpose was practical as much as beautiful. Botanists tested which European crops and plants could survive here. They also collected Australian plants and sent seeds and specimens back to Britain, where scientists were eager to study this strange new flora.

Walk toward the harbour and follow the curve of the sea wall. The path leads out along a headland to a sandstone shape cut into the rock. This is Mrs Macquarie's Chair. Convicts carved it from the living rock for Elizabeth Macquarie, the governor's wife. Locals say she liked to sit here and watch for ships arriving through the harbour heads, bringing letters and news from home. It is one of the best views in Sydney, and one of the oldest.

Now turn and look at the stone all around you. Much of Sydney's early city was built from this same honey-coloured sandstone. It glows almost orange in late afternoon light. Up close, you can see layers and swirls in the rock, laid down by ancient rivers long before people arrived. The sea wall, the steps and the old garden edges all use it. Run your hand along it, and you can feel how soft and sandy it is.

As you move inland, the garden opens into a series of different rooms. There are wide lawns where office workers eat lunch on the grass. There are shady groves of tall fig trees, with great buttress roots spreading across the ground like folded curtains. There are beds of bright flowers that change with the seasons. Because Sydney rarely gets frost, plants from many warm parts of the world grow here outdoors, side by side.

One of the oldest parts of the garden is the Palm Grove. Here, tall palms from many countries stand in a cool, dim space under a high green canopy. For many years, this grove was also home to a large colony of grey-headed flying foxes — big fruit bats that hung from the branches by day. They damaged many old trees, so in the early 2010s the garden encouraged them to move elsewhere. The trees have slowly recovered since.

Here is a second surprise. Somewhere in this garden grows a Wollemi pine. Until 1994, scientists knew this tree only from fossils. Many believed it had disappeared millions of years ago. Then a park ranger found a small group of living trees in a remote, steep canyon in the Blue Mountains west of Sydney. The wild location is kept secret to protect them. Specimens like the one here let visitors see a living fossil without risking the wild trees.

For something more modern, look for The Calyx. It opened in 2016, to mark two hundred years of the garden. The building has a curved glass wall and a large indoor space for changing plant displays. One of its main features is a tall green wall, covered with thousands of living plants growing vertically. The exhibitions change over time, so what you see inside depends on when you visit. It is a good place to shelter on a hot or rainy day.

The garden also sits beside some important buildings. Just inside its edge stands Government House, a grand sandstone building with turrets, built in the nineteenth century as the governor's residence. Nearby is the Sydney Conservatorium of Music. Its castle-like central building began life as stables for the governor's horses, designed by the convict architect Francis Greenway. On a quiet day, you may hear students practising. Piano or violin music drifts across the lawns.

And notice the people around you. Joggers circle the harbour path in the early morning. Families spread picnic rugs under the fig trees. Couples stop for photographs with the Opera House behind them. Birds are everywhere too — sulphur-crested cockatoos with their loud, harsh calls, white ibis walking slowly across the grass, and small wrens darting between the bushes. This is a scientific garden, but it is also Sydney's backyard, used every single day.

Before you leave, find a bench or a patch of grass and simply sit. Look out across Farm Cove at the ferries crossing the water. Think about the layers under your feet — Gadigal fishing grounds, a failed first farm, two centuries of careful planting. As you walk on, notice the sandstone under your shoes, the cockatoos overhead, and the smell of salt and leaves. The garden keeps growing, quietly, one season at a time.