The PHyS-IHRF2026 “International Symposium on Physical Height Systems and the International Height Reference Frame” will be held in Riyadh, Kingdom of Saudi Arabia from 7 to 9 April 2026. It focuses on methods for observing, estimating and interpreting the Earth’s gravity field and the geoid with special emphasis on height systems, physical height determination and the realization of the International Height Reference System (IHRS) into the International Height Reference Frame (IHRF). PHyS-IHRF2026 is a Joint IAG Symposium co-organized by IAG SC2.2 “Geoid, Physical Height Systems and vertical datum unification”, SC2.4 “Gravity and Geoid”, the International Gravity Field Service (IGFS) and the Global Geodetic Observing System (GGOS).

Scientific Organizing Committee:

George Vergos (SC2.2 Chair, IHRF CC director, IGFS CB Director)
Rossen Grebenitcharsky (SC2.2 Vice-Chair)
Riccardo Barzaghi (IGFS President)
Laura Sanchez (GGOS President)
Hussein Abd-Elmotaal (SC2.4 Chair)
Rene Fordberg
Zuheir Altamimi 

Local Organizing Committee:

AlShahrani Sultan Falah
Mohammed AlArjani
Mashael AlHarbi
Saad AlQahtani
Abdulmohsen AlDosari
Saleh AlFaris
Eslam Abdulsamie