Ritmeyer is known for the "solid scientific research" he has done on the archaeology and architecture of the Temple Mount in Jerusalem. He discovered archaeological evidence for the location of Solomon's Temple, the emplacement of the Ark of the Covenant on the Foundation Stone, and the location of the platform as extended in the First Temple period, probably during the time of Hezekiah described as a square of 500 cubits in Mishnah Middot 2.1. He has demonstrated that one of the steps leading to the Dome of the Rock is actually the top of a remaining stone course of the pre-Herodian Western Wall of the Temple Mount platform.
Ritmeyer is known for his architectural models of the buildings of ancient Jerusalem. His models of the historical Jewish Temples have been exhibited at museums including the Yeshiva University Museum in New York and the Siegfried H. Horn Museum at Andrews University, Michigan.
Ritmeyer has published several books, some together with his wife, Kathleen, including:
- Jerusalem at the Time of Jesus
- The Ritual of the Temple in the Time of Christ
- Secrets of Jerusalem's Temple Mount (1998)
- Jerusalem in the Year 30 AD
- Jerusalem in the Time of Nehemiah
- The Quest: Revealing the Temple Mount in Jerusalem
- From Sinai to Jerusalem: The Wanderings of the Holy Ark
- The Temple and the Rock
- "How We Lost the Temple Mount," Hershel Shanks, Moment (magazine), June 2002.
- Gershom Gorenberg, The End of Days (Oxford: OUP, 2002), p. 78
- 'Architect Claims He Has Pieced Together Old Biblical Puzzle' in Los Angeles Times, Jan 6, 1996
-  Archived May 1, 2008, at the Wayback Machine
- "Siegfried H. Horn Museum - Andrews University". Andrews.edu. Retrieved 2015-06-01.
- Eric H. Cline, The Quest (book review), Biblical Archaeology Review, "Revealing the Temple Mount in Jerusalem," 12 January 2012.
- "Getting serious about the Ark of the Covenant," Gabriel A. Sivan (book review), Jerusalem Post, 21 July 2000.