The Ionic-style building at Garni, 5.5 miles slightly southeast of Yerevan, has been and is still described as a pagan temple. It may well be, but it is rather small (if a temple, then it was more of a private shrine) and at least one scholar doesn't think it was built as a temple. This particular photo (a larger version of which is below) was taken by Gerald Ottenbreit Jr. on Sept 13, 1997.
For more information on Garni, see:
Hnahitakan peghoisnere hayastanoim [sic--it probably should be peghusnere hayastanum], no. 15: Garni (Erevan: Haykakan SSH Gitutyunneri Akademiayi Hratarakchutyun).
Arakelian, B.N. "Znachenie raskopok v Garni dlya izuchenia kultury drevne Armenii" [Importance of the Excavations in Garni for the Study of the Culture of Ancient Armenia], Vestnik Drevnei Istorii (Moscow) (1953).
Arakelian, B.N., E.V. Khanzadian, and Zh.D. Kachatrian. Garni, 5 vols. (Erevan: Haykakan SSH Gitutyuneri Akademiayi Hratarakchutyun, 1951-[1972?]).
Derenik Episkopos [Poladian]. Hayastan: Garni alpom (Beirut, 1959).
Grigorian, A. and N. Stepanian. Erevan, Garni, Gegard, Echmiadzin, Ashtarak (Moscow: Izdatelstvo "Isskusstvo," 1985.
Manandyan, Hakob. Garnii Hunaren ardzanagrutyune ev Garnii hetanosakan tachari karutsman zhamanake (Erevan: Pethamalsarani Hratarakchutyun, 1946).
Petrosyan, H.L. Garnin IX-XIV darerum, ed. B.N. Arakelyan (Erevan: Haykakan SSH GA Hratarakchutyun, 1988).
Sahinyan, A.A. Garni-Geghard (Erevan: "Sovetakan Grogh," 1978).
________. Garnii antik karuytsneri chartarapetutyune (Erevan: Haykakan SSH GA Hratarakchutyun, 1983).
Sainian, A.A. Arkhitektura antichnykh sooruzhenii Garni (Erevan: "Sovetakan Grokh," 1988).
Sainian, A. Garni i Gegard (Moscow: "Isskusstvo," 1958.
Sainian, Aleksandr. Teorii Vitruviia o stroenii khramov i antichnyi khram v Garni: [Doklad]: II Mezhdunarodnyi simpozium po armianskomu iskusstvu (Erevan: Izdatelstvo AN ArmSSR, 1978).
Sainjar, Aleksandr Aramovic. Arkhitekturnye panjatniki Garni i Gegarda
(Erevan: "Izdatelstvo "Aiastan," 1969).
(Sahinyan, Sainian, and Sainjar are varients of the same name).
Sekoyan, V.G. Garni, Gehard / Garni, Gekhard (Erevan: "Hayastan," 1987).
Ter-Martirosov, Feliks. Garni amrotsi tachara: Hereon, vkayaran (Erevan: Razmavarakan ew Azgayin Hetazotutyunneri Haykakan Kentron, 1995).
Trevor, K.V. Ocherki po istorii kultury drevnei Armenii, II v. ddo N.E.-IV v. N.E. (Moscow: Izdatelstvo Akademii Nauk SSSR, 1953).
Wilkinson, R.D. "A Fresh Look at the Ionic Building at Garni," Revue des Etudes Armeniennes, n.s. XVI (1982), pp. 221-244.