Commanding expansive ocean views, this windswept national park on the peninsula’s western tip was a seasonal base of its traditional owners, the Boon Wurrung people. After colonisation, a Quarantine Station was established here in 1852. Fort Nepean, which played an important role in defending Australia from military threat, was built in stages from the late 1870s. Original gun emplacements remain there, as do the 50-odd heritage buildings that made up the Quarantine Station.
There are a number of scenic walking and cycling trails in the park; gnarled Moonah trees (Melaleuca lanceolata) bent by the strong winds dot most of the landscape and local fauna including echidnas and wallabies can be spotted. Coles Track links the Quarantine Station with Gunners Cottage and Fort Nepean. En route keep an eye out for the Harold Holt memorial, the site where Australia's former prime minister remarkably disappeared here after a swim in December 1967.
The visitor centre in the Quarantine Station offers walking maps, or hire a bike (per three hours standard/electric bike $19.40/43.70) – they book out, so arrive early to avoid disappointment. Audio tours of Fort Nepean, the Quarantine Station and the park can be downloaded from the Parks Victoria website or the iTunes Store.
There is a large car park at the Quarantine Station. To get to the fort you can park at Gunners Cottage, from where it's a 2.6km walk or bicycle ride. Alternatively a hop-on/hop-off wheelchair-accessible shuttle bus travels between the quarantine station and the fort (adult/child return $12/8) operating every 30 minutes between 10.30am and 4pm. This connects with the Portsea public bus stop (bus 788 to/from Frankston) three times daily; check the Parks Victoria website for details.