The longest of these is known as Shanti Parva and talks about what happens once the Kurukshetra War is over. As a subsection of Shanti Parva, there is a section known as Moksha Dharma Parva. I think one will form a better appreciation of the Bhagavad Gita if one reads the Moksha Dharma Parva as a companion text. One will have a better understanding of what the Bhagavad Gita means by yoga.
