Apache Cassandra 3.0 release notes
Release notes for the Apache Cassandra 3.0.
The latest version of Apache Cassandra 3.0 is 3.0.19.
The CHANGES.txt describes the changes in detail. You can view all version changes by branch or tag in the drop-down list on the changes page.
New features, improvements, and notable changes are described in What's new in Apache Cassandra 3.0.