The people of Thamud are a tribe mentioned in the Qur'an about whom a substantial amount is known. Historical sources confirm that a people known as the Thamud existed many years ago. It is believed that the people of al-Hijr referred to in the Qur'an are actually the same people as Thamud, because another name for Thamud is "Ashab al-Hijr."
That being the case, the word "Thamud" may be the name of a people and al-Hijr one of the cities they founded. In fact, this is exactly what is suggested by the descriptions of the Greek geographer Pliny, who wrote that Thamud lived in places called Domotha and Hegra, the present-day city of Hijr.
Mada'in Saleh Arabic: مدائن صالح "Cities of Saleh", also called Al-Hijr ("rocky place"), is an ancient city located in northern Hejaz (modern day Saudi Arabia). In ancient times the city was inhabited by Thamudis and Nabateans and was known as Hegra.
Some of the inscriptions found in the area date back to the 2nd millennium BC. However, all the remaining architectural elements are dated to the period of the Thamudi, Lihyan and Nabatean civilizations, between the 1st millennium BC and the second century AD.
In 2008, UNESCO proclaimed Mada'in Saleh as a site of patrimony, becoming Saudi Arabia's first World Heritage Site.
Thamud curved their houses in these strong mountains
(Al-Hijr) The Rocky village
5000 years ago, there was a nation lived here called Thamud, they were one of the strongest nations who came to this earth, they curved there houses in these strong mountains. They worshiped idols, and disbelieved in God the only creator of the universe. So prophet Saleh warned them and called them to "worship the only one God". They told him, if you are really a messenger from God; can you bring out of this strong rock a pregnant Camel, so that we can drink from its milk?.
The rock split and a camel with the same specifications for which they asked came out, but yet they denied and refused.
Indeed, the Qur'an refers to their expertise in stonework thus:
(وَاذْكُرُواْ إِذْ جَعَلَكُمْ خُلَفَاءَ مِن بَعْدِ عَادٍ وَبَوَّأَكُمْ فِي الأَرْضِ تَتَّخِذُونَ مِن سُهُولِهَا قُصُورًا وَتَنْحِتُونَ الْجِبَالَ بُيُوتًا فَاذْكُرُواْ آلاءَ اللّهِ وَلاَ تَعْثَوْا فِي الأَرْضِ مُفْسِدِين). (الأعراف : 74)َ
[Salih said to his people,] (Remember when He appointed you successors to 'Ad and settled you in the land. You built palaces on its plains and carved out houses from the mountains. Remember Allah's blessings and do not go about the earth, corrupting it). (Qur'an, 7:74)
(The people of al-Hijr denied the Messengers. We brought them Our Signs but they turned away from them. They carved out houses from the mountains, feeling safe, but the Great Blast seized hold of them in the morning, so all that they earned was of no use to them). (Qur'an, 15:80-84)
Harun Yahya: Miracles of the Quran