## 2 Literature Review on the Australian HSR Risks and Barriers
### Alluring Potential of High-Speed Rail in Australia  
Complex megaprojects, such as HSR, have a profound impact on societal structures. This impact spans technological, economic, political, and aesthetic dimensions [14; 15]. As of 2018, 22 countries had established HSR, with an additional 13 countries poised to join [16]. Yet, HSR in Australia only appears in feasibility studies. Recent studies, like the 2013 High-Speed Rail Study, highlight HSR's potential to reduce travel times, such as the 40 min journey between Sydney and Newcastle [5] compared to over 120 min by road and 180 min by air (including travel to and from airports). These improvements enhance connectivity and offer opportunities to address housing challenges through satellite developments [3]. These are factors that the HSRA must capture in its upcoming feasibility study to ensure success. A Sydney to Newcastle HSR alignment further stimulates business growth along the Eastern corridor, attracting both tourists and business travellers, as highlighted by [PERSON], Minister for Infrastructure [17]. Authors [PERSON] and [PERSON] [18] agree that the UK's HSR alignment improved accessibility and attractiveness for tourists by reducing travel times and enhancing connectivity between destinations. Hence, similar benefits can be expected for Australia's Sydney-to-Nastenburg alignment.  
[PERSON] [19] further notes that introducing HSR transforms traditional commuting methods and contributes to the aesthetic subline, as argued by [PERSON] [14]. [PERSON] states that the shift would transform conventional practices like fly-in-fly-out and drive-in-drive-out to a streamlined and comfortable train-in-train-out commuting system [19]. Authors [PERSON] et al. [19; 20] further attest to this, where their study conducted in China  
Figure 2: Research structure.  
concluded that the transition to HSR reduced reliance on traditional commuting methods such as car and air travel. Similarly, an Australian government study found that HSR could lead to a \"positive transformational effect on how most Australians live, work, and travel\" and \"has the potential to be an integral part of Australia's future\" [21]. The evidence of HSR's benefits to commuters is widely argued and accepted in the literature.  
The above-improved connectivity also contributed to the wide-reaching economic benefits of HSR, such as increased productivity, labour market expansion, and regional economic growth, argued [PERSON], [PERSON] and [PERSON] [18,19]. The broader economic benefits stemming from these societal impacts are substantial. For instance, Spain's comprehensive HSR network over 24 years yielded substantial savings of approximately $4.286 billion due to reduced pollution, accidents, and positive climate change impacts [1,22]. In the Australian context, a study by the University of Wollongong emphasised the potential for HSR to generate a \"massive boost to the Australian economy that would be difficult to achieve in any other way\" [23]. Hence, the literature agrees that the benefits of an HSR alignment are substantial, yet the reasons for the lack of implementation are still unknown.