During April 3-6, 2023 the University of Warwick hosted the 3rd World Congress on Undergraduate Research (WorldCUR) alongside the British Conference of Undergraduate Research (BCUR), combining this international event with a national conference for the first time. The events brought together undergraduate researchers from around the world to present their ideas in international and interdisciplinary spoken and poster sessions. The planning of the events was disrupted and shaped by the COVID-19 pandemic, which meant a postponement of a year and, ultimately, led to two large in-person events, the first that most delegates had attended in many years. Feedback on the events was strong. This article discusses the organization and planning of the events, the evaluation feedback and the impact of the pandemic on WorldCUR-BCUR 2023.