Sanskrit Language is believed to have no written native script. History says Brahmi Script was used for Sanskrit Language during the reign of legendary Emperor Ashoka which was around 3rd century BC. But there are some claims that Brahmi script was even used before period of Ashoka.
Wiki says Nagari Script was developed from Brahmi scripts and Nagari Script is very similar to Devanagari. But Brahmi Script appears very different from Nagari script. See this page and this page and compare the scripts.
And ॐ (OM) Parvat is a mountain in Himalayas which is situated partially in India and Nepal. Snow clad OM parvat looks like Shabhda Brahman ॐ.
Image Credits: Wikimedia Commons
OM symbol is generally written as ॐ in Devanagari. OM in OM Parvat is similar to "OM" of Nagari Script and Devanagari Script. Himalayas were formed 50 million years ago and so was the OM Parvat. Even according to Mythology, Himavat, personification of Himalayas and father of Parvati and Ganga was born at the beginning of Vaivasvara Manvantara as he was present during the marriage of Shiva and Parvati. So, OM Parvat was an ancient one.
So, Is Brahmi Script older than Devanagari Script? If yes, how this can be reconciled with OM Parvat? Is OM symbol same for all Scripts, which I think not correct? I asked a question how OM is represented in Brahmi Script here.