March for Life - The March takes place every year in January in Washington, D.C. 
https://marchforlife.org/national-march-for-life

NCYC (National Catholic Youth Conference) – El Camino / The Way November 14 – 16, 2024 / Long Beach, CA
https://ncyc.us

Steubenville STL Mid-America – This high-energy youth conference is held every year in July and takes place on the campus of Missouri State University in Springfield, MO.
https://steubystl.com/

World Youth Day – The next World Youth Day will be held in Seoul, South Korea 2027
https://worldyouthday.com/