<page_title> List of rivers by length </page_title> <section_title> List of rivers longer than 1000 km </section_title> <table> <cell> 7. <col_header>  </col_header> </cell> <cell> Ob–Irtysh <col_header> River </col_header> </cell> <cell> Russia, Kazakhstan, China, Mongolia <col_header> Countries in the drainage basin </col_header> </cell> </table>
The Ob River is a river in Russia, and is the world's seventh-longest river.