Vanvas is a Sanskrit term meaning residence (vās) in a forest (van). While it can be undertaken voluntarily, it usually carries a connotation of forced exile

Exile

Exile means to be away from one's home , while either being explicitly refused permission to return and/or being threatened with imprisonment or death upon return...

 as a punishment. It commonly figures as a harsh penalty in ancient Hindu

Hindu

Hindu refers to an identity associated with the philosophical, religious and cultural systems that are indigenous to the Indian subcontinent. As used in the Constitution of India, the word "Hindu" is also attributed to all persons professing any Indian religion...

 epics (such as the Ramayan and Mahabharat) set in a time, thousands of years ago, when much of the Indian subcontinent

Indian subcontinent

The Indian subcontinent, also Indian Subcontinent, Indo-Pak Subcontinent or South Asian Subcontinent is a region of the Asian continent on the Indian tectonic plate from the Hindu Kush or Hindu Koh, Himalayas and including the Kuen Lun and Karakoram ranges, forming a land mass which extends...

 was a wilderness

Wilderness

Wilderness or wildland is a natural environment on Earth that has not been significantly modified by human activity. It may also be defined as: "The most intact, undisturbed wild natural areas left on our planet—those last truly wild places that humans do not control and have not developed with...

.

When vanvas is self-imposed, it can imply seclusion from worldly affairs to focus on spiritual matters, as in the case of ashram

Ashram

Traditionally, an ashram is a spiritual hermitage. Additionally, today the term ashram often denotes a locus of Indian cultural activity such as yoga, music study or religious instruction, the moral equivalent of a studio or dojo....

s (hermitages) established by ancient rishi

Rishi

Rishi denotes the composers of Vedic hymns. However, according to post-Vedic tradition, the rishi is a "seer" to whom the Vedas were "originally revealed" through states of higher consciousness. The rishis were prominent when Vedic Hinduism took shape, as far back as some three thousand years...

s. When imposed as a punishment, it carries an implication of enforced isolation from society and exposure to life-threatening situations (the elements and wildlife).