<p>This study developed and validated an Immersive Virtual Reality Travel Application (IVRTA) for older adults using a familiarity design approach that emphasizes representation (interface appearance), manipulation (interface interaction), and guidance (information guidance). A total of 86 participants aged 65 years and above were recruited. We employed a 2 × 2 between-groups experimental design comparing two interface types—Dual-Layer Three-Dimensional (D3D) vs. Single-Layer Three-Dimensional (S3D)—and two guidance types—Anthropomorphic Virtual Agent (AVA) vs. Non-Anthropomorphic Virtual Agent (NAVA). The study examined the effects of interface design and guidance style on older adults’ user experience and explored the mediating pathways through which familiarity design influences their continuous intention (CI). Results showed that the D3D user interface significantly enhanced self-efficacy, perceived ease of use, perceived usefulness, and CI among older adults. Additionally, an AVA significantly improved perceived ease of use and CI and was associated with longer usage duration. Mediation analyses further indicated that the D3D user interface indirectly facilitated CI through increased self-efficacy and perceived ease of use. At the same time, the AVA influenced CI primarily via the perceived ease of use pathway. The study suggests that applying familiarity design to the design of IVRTA will assist older adults in overcoming digital barriers, enabling them to enjoy the rich experiences that IVRTA provides, which will improve the quality of their later life and contribute to the overall development of the IVRTA industry and the building of smart, healthy age-friendly environments.</p>