Place · Smarta · South India · Davanagere district, Karnataka, at the Tungabhadra–Haridra confluence
Harihar
Hoysala-period temple town whose Harihareshwara shrine (built about 1223–24 by the minister Polalva) enshrines the combined Vishnu–Shiva image. Its charter says Vishnu and Shiva merged here to kill the demon Guha, whom Brahma's boon had made impossible for either to kill alone.
Sources: Harihareshwara Temple (Harihar, Karnataka) — Wikipedia · see Harihar's web