Dhanya Sanal, 38, climbed the Agasthyakoodam mountain in the southern state of Kerala months after a high court revoked the ban.
The peak has a statue of a Hindu sage, whom local tribespeople say is celibate. So, they are opposed to women going to the peak.
Ms Sanal however said that she was not stopped by locals or protesters.
She told the BBC that she had been "ready to turn back" in case the tribespeople stopped her. While she did encounter protesters, she said they did not prevent her from continuing her trek.
In November, the high court in Kerala ruled that women could trek to the 1,868m (6,128ft) peak. The court said that restrictions on trekking cannot be based on gender after a women's group petitioned the court.
"We have moved one step ahead in ending gender discrimination in Kerala," Divya Divakaran, a member of the women's group that petitioned the court, told the BBC.
The court rejected the claim made by tribespeople, who live at the foothills, that the verdict hurt their beliefs.
They said they worshipped the sage, Agastya, and did not want women in the vicinity of his idol as that amounted to disrespecting his celibacy.
Located in India's Western Ghats, Agasthyakoodam is the second highest peak in Kerala. The terrain is full of steep rocks and the trail is inside a thick forest. Trekkers often take two or three days to scale the peak.
"It is an extremely tough terrain that demands extra physical fitness," Ms Sanal told the Times of India newspaper, adding that it is almost "undoable" for woman older than 45.
She was the only woman in a group of 100 trekkers. The group was accompanied by two female forest officials.
Officials told the BBC that more than 100 women have registered for treks in the coming weeks.
Earlier this month, two women made history in Kerala by entering a prominent Hindu shrine, following months of protests against their entry.
The Sabarimala temple was historically closed to women of "menstruating age" - defined as between 10 and 50. Devotees believe that the deity is an avowed bachelor and the ban on women of "menstruating age" was in keeping with his wishes.
Hinduism regards menstruating women as unclean and bars them from participating in religious rituals.
The women's entry to the shrine prompted massive protests across Kerala.
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