Assam State Museum, also known as Assam Rajyik State Museum is in Guwahati.
It has an extensive collection of artifacts and sculptures dating back to the 5th-12th century to the new artifacts from the World War II.
This is a good place to know about the history of the North-east India.
It has sections like sections like manuscripts, arms and ammunition, terracotta, epigraph, metallic sculptures and natural History.
The entry ticket for adults is INR 20/-