Kufa was considered as a major centre for Hadith Sciences from the time Caliph 'Umar (d.24 A.H.) sent 'Abd Allah ibn Mas'ud (d.32 A.H.), the sixth person to embrace Islam, as a tutor to the people of Kufa. The approximate number of students who attended ibn Mas'ud's discourses were 4,000. Besides ibn Mas'ud, there were other illustrious companions of the Prophet (SAW) who resided in Kufa, prominent among them being Abu Musa al-Ash'ari (d.52 A.H.), Salman al-Farsi (d.35 A.H.), 'AmmAr b. Yasir (d.37 A.H.), Huzaifa b. Yaman (d.35 A.H.) and S'ad b. Abu Waqqas (d.55 A.H.). Therefore, on one occasion referring to Kufa, 'Ali b. Abu Talib (d.40 A.H.), the fourth Caliph of Islam remarked, "The companions of ibn Mas'ud are the lanterns of this Umma (Muslim community)". Since the famous traditionists were stationed in Kufa, Imam Bukhari said that he cannot even count how often he accompanied the traditionists to Kufa and Baghdad. That Kufa was a major centre of learning and contained many scholars is evident from the fact that Tirmidhi reported traditions from forty-two Kufan teachers. In his compilation he used more reportings of Kufan teachers in comparison to the number of reportings used of teachers from any other town.
Baghdad was also considered as a major centre of learning. A.J. Wensinck has mentioned that Ahmad b. Hanbal (d.241 A.H.) was Tirmidhi's teacher. According to the most reliable sources, Tirmidhi never went to Baghdad and did not attend any lectures of Ahmad b. Hanbal. Furthermore, Imam Tirmidhi, whenever narrating a sanad wherein the name of Ahmad b. Hanbal is mentioned, always names a transmitter between himself and Ahmad b. Hanbal, that is, Imam Tirmidhi never directly narrated from Ahmad b. Hanbal anywhere in the Jami'. Hence, a meeting between the two was highly improbable.
Another great centre of learning was Basra. The companions of the Prophet (SAW) who resided here, were Anas b. Malik (d.91 A.H.), 'Abd Allah b. 'Abbas (d.68 A.H.) and 'Imran b., Husain (d.52 A.H.). During the time of Imam Tirmidhi, Zayd b. Akhzarn (d.257 A.H.) was the famous traditionist of Basra. He was the teacher of Imam Bukhari, Imam Nasa'i, Imam Abu Dawud, Imam Tirmidhi and Imam ibn Maja. Other famous traditionists of Basra were 'Abbas 'Anbari (d.246 A.H.), Muhammad b. Bashshar Bundar (d.252 A.H.), Muhammad b. al-Muthanna (d.252 A.H.) and Muhammad b. M'amar (d.250 A.H.). Each of the six canonical traditionists attended the discourses of the above mentioned traditionists.
Imam Tirmidhi's native land Khurasan was also considered as an intellectual capital. It was known as Madina al-Rijal - "The City of Men", referring to the large number of traditionists who resided there.