Dengue virus (DENV) transmission is ubiquitous throughout the tropics with the Asia-Pacific region responsible for greater than 70% of the current global dengue disease burden. DENV serotype and genotype data is lacking in many parts of this region, limiting our attempts to understand the observed patterns of hyperendemicity and disease severity. Many countries in the Southeast Asia and Western Pacific region are popular tourist destinations, and dengue has been identified as a cause of travel-related illness in people returning from endemic countries. We sequenced the E gene of DENV isolated from travellers returning to Western Australia from 7 countries throughout Asia between 2010 and 2012. We identified a diverse array of multiple co-circulating DENV1-4 viral lineages with the majority originating in Indonesia, predominantly Bali, a popular travel destination for Australians. Most viruses were closely related to lineages known to have circulated in Indonesia for some time, indicating that this geographic region serves as a major hub for dengue genetic diversity. Most interestingly, we identified a new lineage of DENV-2 (Cosmopolitan genotype) that emerged in Bali in 2011–2012 which should be monitored. Travellers may act as sentinels and provide important information on DENV genotypes and linages circulating in countries where locally generated detailed genetic data may not be available.