Dwarka is often identified with the Dwaraka Kingdom, the ancient kingdom of Krishna and is believed to have been the first capital in India (Bharatawarsha)
Basically, Vraja is the land of Krishna. If you really want to understand the pastimes of Krishna, you have to know Vraja. And if you want to know the significance of Vraja, you have to understand Krishna’s pastimes. Krishna was born in Mathura 5,000 years ago but lived in Gokula for three years, then moved to Chatikara and Vrindavan for three years, then lived in Nandagram for three years, and from age 10 to 28 He lived in Mathura. After this He moved to the western coast of India where He lived in Dwaraka for over 96 years.