The great epic of the Bhāratas
Mahabharata
महाभारतम्
The longest poem ever composed — the rivalry of the Pāṇḍavas and Kauravas, the wisdom of Kṛṣṇa, and within it the Bhagavad Gītā. Read here in Kisari Mohan Ganguli’s prose, the only complete English rendering in the public domain — beginning with the Ādi Parva (the origins) and the Sabhā Parva (the assembly hall and the fateful game of dice), section by section.
More to come
The remaining sixteen books — from the Vana Parva of the forest exile through the Bhishma Parva (which holds the Gītā) to the Svargārohaṇa Parva — are being added as clean, proofread text becomes available. The complete Bhagavad Gita is already here in full under the Vedic Corpus.
English prose translation by Kisari Mohan Ganguli, The Mahabharata of Krishna-Dwaipayana Vyasa (1883–1896), public domain, via Wikisource. Footnotes from the original edition are omitted.