Narasimha Avatar killed Hiranyakasipu at Multan, Pakistan

Hiranyakashipu, became king of the daityas after his brother Hiranyaksha was was killed by Varaha Avatar. Both brothers were born to Sage Kasyap and Diti.
Hiranyakasipu had a wife Kayādhu, and they had four sons – Saṁhlāda, Anuhlāda, Hlāda and Prahlāda.
After his brother’s death, Hiraṇyakaśipu developed hatred towards Vishnu and he worshipped Brahma along with Goddess Chhinnamasta (छिन्नमस्ता) and defeated devas.
It is believed that both brothers were born at a place, which is today called as Hindaun (Rajasthan, India). Hiranyakasipu established his capital at Kasyapapuri, a city found after his father.
To attack Vishnu, Hiranyakasipu did severe penance for gaining powers and Brahma appears before him to offer a boon of his choice. But when Hiranyakashipu asks for immortality, Brahma refuses. Hiranyakashipu then makes the following request:

O my lord, O best of the givers of benediction, if you will kindly grant me the benediction I desire, please let me not meet death from any of the living entities created by you.
Grant me that I not die within any residence or outside any residence, during the daytime or at night, nor on the ground or in the sky. Grant me that my death not be brought by any being other than those created by you, nor by any weapon, nor by any human being or animal.
Grant me that I not meet death from any entity, living or nonliving. Grant me, further, that I not be killed by any demigod or demon or by any great snake from the lower planets. Since no one can kill you in the battlefield, you have no competitor. Therefore, grant me the benediction that I too may have no rival. Give me sole lordship over all the living entities and presiding deities, and give me all the glories obtained by that position. Furthermore, give me all the mystic powers attained by long austerities and the practice of yoga, for these cannot be lost at any time.

When he realized that his youngest son Prahlada turned into a devotee of Vishnu, Hiranyakasipu tries to change his mind. When that attempt fails, he tries to kill his own son through different methods but fails. That including burning him along with Holika (Holika Dahan and Holi festival started here).
After multiple failures to poison his son to death, Hiranyakasipu finally points to a nearby pillar and asks if ‘his Vishnu‘ is in it:

O most unfortunate Prahlada, you have always described a supreme being other than me, a supreme being who is above everything, who is the controller of everyone, and who is all-pervading. But where is He? If He is everywhere, then why is He not present before me in this pillar?

Prahlada then answers, He was, He is and He will be anywhere, everywhere.
Narasimha emerges from Pillar
Hiranyakashipu, unable to control his anger, smashes the pillar with his mace. A tumultuous sound is heard, and Vishnu in the form of Narasimha appears from the broken pillar and moves to attack Hiranyakashipu in defence of Prahlada. This happened on vedic lunar day of Vaisakha Sukla Chaturdasi (day before full moon in month of Vaisakha).
Vishnu has chosen here to appear in the form of Narasimha in order to be able to kill Hiranyakashipu without violating the boon given by Brahma. Hiranyakashipu cannot be killed by human, deva or animal, but Narasimha is none of these, as he is a form of Vishnu (a deva) incarnate as part human, part animal. He comes upon Hiranyakashipu at twilight (when it is neither day nor night) on the threshold of a courtyard (neither indoors nor out), and puts the demon on his thighs (neither earth nor space). Using his nails (neither animate nor inanimate) as weapons, he disembowels hiranyakasipu with nails and kills him.
Narasimha Killing Hiranyakasipu
Traditional hindus do not cut nails at twilight time, as a mark of respect for Lord Narasimha.
At one stage, Hiranyakasipu was so strong and people in his generations were so huge, that in later generation, Ravana failed to uplift and ear ring of Hiranyakashipu.

Even after Hiranyakashipu’s death, none of the gods and demigods present are able to calm Narasimha’s fury, not even Siva. So all the gods and goddesses call His consort, the goddess Lakshmi, but she is also unable to do so. Then, at the request of Brahma, Prahlada is presented to Narasimha, who is finally calmed by the prayers of his devotee.
Narasimha with Prahlada

First Lord Narasimha Temple built at Multan, Pakistan

At the pillar, from where Narasimha appeared, Prahlada later built the first ever temple for Lord Narasimha. That place was called Mulasthana (Moola-Sthana), which means originating point (of Narasimha) and Vaisakha Sukla Chaturdasi is celebrated as Narasimha Jayanti.
After his father, Prahlada was crowned as emperor and ruled from that place. Prahlada’s son was Virochana, whose son was King MahaBali, who was sent to Patala (South America), by Vishnu in the form of Vamana.
Multan Prahladapuri Temple Ruins
Over a period of time, Mulasthana was capital of the Trigarta Kingdom ruled by the Katoch dynasty at the time of the Kurukshetra War. Over a period of time, Mulasthana became Multan and it was the centre of a solar-worshipping cult that was based at the ancient Multan Sun Temple.
This place is mentioned by Greek historians since 6th century BCE.

Prahladapuri Narasimha Temple, Multan – destroyed in 1992

After Babri Masjid in India was demolished, multiple hindu temples were attacked and destroyed in Pakistan. Ancient Prahladapuri Temple in Multan was one of them.
Right now the ruins are adjacent to the Shrine of Bahauddin Zakariya.
Multan Prahladapuri Temple Before and After 1992

Prahladapuri Mandir and Bahaduddin ZakariaThis temple was rebuilt by many kings multiple times. Last rebuilt was in 1810 CE, when the area was under the rule of Sikhs. However, Alexander Burnes, who visited the temple in 1831, said that he found it deserted and without a roof.
Later in year 1849, when British laid siege of Multan Fort against Mul Raj, a shell fired by British army fell on gunpowder store within the fort, thus destroying almost all of the fort except the mausoleums of Bahauddin Zakaria and his sons and the Prahladpuri temple complex.
Alexander Cunningham described this temple as it was seen in 1853 by him who wrote that: “It was a square brick building with some very finely carved wooden pillars for the support of the roof“.

Multan also had an ancient Sun Temple, which was destroyed by mob attack in 1992.

Present temple was first built in 1861 by Mahant Bawl Ram Das at cost of Rs.11,000 by way of public donation and again in 1872 by the subsequent Mahanta of Prahladpuri temple with donations from Thakur Dawara Fateh Chand Tanksalia and other Hindu citizens of Multan. But in 1881, while renovation of temple a major dispute arose between Hindus & Muslims over the height of shikhara of the temple and dome of the adjacent mausoleum, which led to riot in which 2 mosques and 22 temples were destroyed.

The British government of Punjab did little to control the mobs and in this riot Prahladapuri temple was also sacked and obliterated. However, the temple was soon rebuilt by then prosperous Hindu community of Multan and was managed by the community, who regulated Mahant of Prahladpuri temple.
After the creation of Pakistan, most Hindus migrated to the newly independent Republic of India and the affairs of temple were managed by minority Hindus of city.
The original idols of Lord Narasimha were taken to India by Baba Narayan Das Batra from Multan and are now placed in a temple at Haridwar.

The cult of Narasimha worship is spread all over the world. Lion faced statues and idols were found in Germany, Egypt, Cambodia etc.
Even the tradition of coronation thrones of ancient Kings having Lions either at base or on arm-rests started with Narasimha coronating Prahlada as Emperor.
In sanskrit, this throne is called Simhasana (Simha = Lion + Asana = Seat).
British Coronation Throne is a Vedic Simhasana.