In the final section of the Uttara Kanda (Book 7 of the Ramayana), the fate of the offsprings of Rama and his three brothers—Lakshmana, Bharata and Shatrughna—is described. Rama had two sons, Kusha and Lava. Kusha became the ruler of the kingdom of North Kosala, located in the north of the Vindhya mountains, and he ruled from a city called Kushavati. Lava became the ruler of South Kosala, and he ruled from a city called Shravati, also called Shravasti. It is believed that Lava founded a city called Lavapuri, today’s Lahore.
Rama’s three bothers had two sons each. Lakshmana’s two sons were Angada and Chandraketu. Angada became the king of Karapatha, and he ruled from a city called Angadiya. Chandraketu became the king of Malla (a kingdom of wrestlers located between Kosala and Videha), and his capital city was Chandrakanta. Bharata’s two sons were Taksha and Pushkara. Taksha became the king of Takshashila, and Pushkara of Pushkaravata. Shatrughna’s two sons were Subahu and Shatrughati. Subahu became the king of Madhura and Shatrughati of Vaidisha.
The Ramayana tells us that after Rama had ruled for 10,000 years, Time (attired as a sage) arrived at his court and informed him that it was now time for him to return to heaven. Rama agreed and on a designated day, along with his brothers, he entered the Vaishnava energy, and he took the form of Lord Vishnu. A large number of his followers, which included humans, apes, serpents, yakshas, and rishis, were allowed to enter the world known as Santanika, which possesses all the qualities of heaven and is only next to Brahma’s world.
Rama’s wife Sita did not follow him into the Vaishnava energy. When she was performing the second Agni Pareeksha (trial by fire to prove feminine purity) that Rama had ordered, the earth opened and goddess earth appeared seated on a celestial throne. She made Sita sit on the throne beside her and they went underground. Thus, at the climax of their earthly lives, Rama and Sita travelled in opposite directions—he went towards heaven, which is the metaphorical north, while Sita went towards the center of the earth, which is the metaphorical south.
The Ramayana is the story of the Surya Vamsha (the Solar Dynasty), whose first proper king was Iksvaku. The Mahabharata is the story of the Chandra Vamsha (the Lunar Dynasty), whose first proper king was Ila. Krishna was born in the Yaduvansh branch of the Lunar dynasty. The story of the Yaduvansh branch is described in the Harivamsa (also known as the Harivamsa Purana). The Ramayana takes place in the Treta Yuga; the Mahabharata in the Dvapara Yuga.