<page_title> 2012 Olympic Marathon Course </page_title> <section_title> The course </section_title> <table> <cell> 1 <col_header> Lap </col_header> <col_header> km </col_header> </cell> <cell> 3.571 <col_header> Distance </col_header> <col_header> mile </col_header> </cell> </table>
The first lap of 2012 Olympic Marathon Course has 3.571 km long.