For the Bahá'ís, Edirne and the houses where Bahá'u'lláh stayed are sacred and they call it "Arz-ı Sır" or "City of Secrets". Edirne has the same meaning for the Bahá'ís as the Ka'ba has for Muslims. Because Baha'u'llah travelled from Iran, which was within the borders of the Ottomans at that time, to Istanbul and then to Edirne in 1864 and lived in Edirne for about 4.5 years.

He also made the first announcement of the religion of Baha'ism to the world from Edirne and declared that the expected Imam Mahdi was sent to him by God. It welcomes visitors from all over the world in every season.