[6] Its original name was just National Park, but it was renamed in 1955 after Elizabeth II, Queen of Australia passed by in the train during her 1954 tour.

The river valleys drain from south to north where they run into Port Hacking, the extensive but generally shallow harbor inlet which forms the northern border of the park.

The geology of the site consists mostly of the Triassic Hawkesbury Sandstone with some sections of the park having the more recent richer Wianamatta shale capping.

Common vegetation on the exposed heaths on the headlands and cliffside paths include Coastal rosemary, darwinia, bracelet honey-myrtle, she-oak, white kunzea, sundew, grass trees, ridged heath-myrtle, snakehood orchids, prostrate forms of coast banksia and long-leaf matrush.

Sections of rare and threatened clifftop grasslands occur along exposed and windy sites which are generally dominated by long-leaf mat-rush and kangaroo grass (Themeda australis).

In Royal National Park, littoral rainforest (often the first type of vegetation destroyed during coastal development) has survived the ravages that occurred elsewhere during the 19th and 20th centuries.

An example of this vegetation occurs in the southern stretch of the Coast Walk, often referred to as the "Palm Jungle", and includes a typical tuckeroo (Cupaniopsis anacardioides) forest, under grown by coastal tea tree (Leptospermum laevigatum) and long-Leaf matrush (Lomandra longifolia).

Soils on plateau land are often up to 2m deep and consist of on sandstone ridges: sandy podsol interspersed with pockets of clay derived.

Small streams are to be found reasonably frequently and understory plants cohabitate with the larger trees, although the terrain is still fairly open and easy to move through.

grass, forest grass trees (Xanthorrhoea arborea), Sydney waratah (Telopea speciosissima), flannel flowers (Actinotus minor as well as Actinotus helianthi), blueberry ash (Elaeocarpus reticulatus), silky hakea (Hakea sericea), variable bossiaea (Bossiaea heterophylla), bonnet orchids (Cryptostylis erecta), hyacinth orchids (Dipodium variegatum/punctatum/roseum), Pomax umbellata, native parsley (Lomatia silaifolia), edible native currants (Leptomeria acida), broad leaved geebungs (Persoonia levis), Sydney golden wattles (Acacia longifolia), gymea lilies (Doryanthes excelsa), various sheo-oaks (Allocasuarina littoralis/distyla/verticillata etc.

Birds that frequent this habitat include Golden whistlers (Pachycephala pectoralis), yellow-tailed black cockatoos (Calyptorhynchus funereus), laughing kookaburra (Dacelo novaeguineae), eastern whipbirds (Psophodes olivaceus), New Holland honeyeaters (Phylidonyris novaehollandiae), eastern spinebill (Acanthorhynchus tenuirostris), rufous whistlers (Pachycephala rufiventris), willie wagtails (Rhipidura leucophrys), superb fairywrens (Malurus cyaneus), crimson rosellas/mountain lowry (Platycercus elegans), yellow-rumped thornbills (Acanthiza chrysorrhoa) and white-browed scrubwrens (Sericornis frontalis).

Other commonly encountered animals in this habitat include native honeybees, wallaroos (Macropus robustus), common echidnas (Tachyglossus aculeatus) as well as other far rarer species such as the koala (Phascolarctos cinereus), the dingo (Canis lupus dingo) or the predatory native marsupial the spotted quoll (Dasyurus maculatus spp.

Impressive groves of turpentine (Syncarpia glomulifera) and blackbutt (Eucalyptus pilularis) trees may be seen growing straight up into the sky forming an open canopy with widely spaced trunks.

In these turpentine forests often hundreds of cabbage palms (Livistona australis) may be seen growing in dense tall thickets which are rarely touched by fire or they may exist as young plants in open grassy spaces which are burnt regularly enough not to form visible trunks.

Birds distinctive to these rich rainforest habitats include Topknot pigeons (Lopholaimus antarcticus), green catbirds (Ailuroedus crassirostris), rufous fantails (Rhipidura rufifrons) and black-faced monarchs (Monarcha melanopsis).

Two interesting birds often encountered in dense scrub or rainforest include the flightless brush turkey (Alectura lathami) and the noise mimicking superb lyrebird (Menura novaehollandiae).

[12] In a zone generally up to 10-25m away from running water grows a distinct vegetation community often containing many rare or threatened species only found along several streams in the world.

Long-finned eels (Anguilla reinhardtii) which migrate from oceanic spawning grounds as babies and adults mature in the creeks and streams of the Royal National Park and can often be seen in the murky depths of pools and ponds along freshwater courses such as the Hacking River.

Mudflats exist along the shoreline of the Royal National Park which is substantial enough to sustain a simplistic system of mangrove woodlands especially along the Port Hacking Estuary with the occasional clump of stunted tree on the seaward coastline in sheltered coves.

These mangroves are important nursery grounds for nearly all major angling fish including yellowfin bream (Acanthopagrus australis), flat-tail sea-mullet (Liza argentea), luderick (Girella tricuspidata) and sand whiting (Sillago ciliata) which are caught in adjoining waters as adults, mangroves also provide rich organic matter to the Port Hacking Estuary by fixing carbon into the river system through the addition of leaves into the thick rich black mud.

A more casual visitor to the mangroves at high tide is the eastern sea garfish (Hyporhamphus australis) which scoots around just an inch from the surface and is virtually invisible unless viewed through a snorkel.

Commonly seen bird species include Eastern curlews (Numenius madagascariensis), striated herons (Butorides striatus), brown honeyeaters (Lichmera indistincta), little egrets (Egretta garzetta), royal spoonbills (Platalea regia), white-faced grey herons (Egretta novaehollandiae), Australasian little bitterns (Ixobrychus dubius), pied oystercatchers (Haematopus longirostris), Australasian pelican (Pelecanus conspicillatus), sacred ibis (Threskiornis moluccus), chestnut teal (Anas castanea) and azure kingfishers (Alcedo azurea).

A series of sandstone rockshelves and rock pools fringe the entire coastline and Port Hacking Estuary Line of the National Park broken on by small sandy beaches and gentle freshwater inlets.

Beds of the primitive sea-squirt cunjevoi (Pyura stolonifera) are common along coastal rockshelves which are covered by high tide and near sea spray.