North London line then it was switched to . Later, it was cut back to . A tunnel, the Hampstead Heath tunnel, runs under Hampstead between and . The line is double track throughout, with a mix of triple and quadruple track between and . The former North Woolwich branch included a section of single track between Custom House and North Woolwich stations, and the Broad Street branch was at one time formed of quadruple track. During the February–May 2010 blockade, the , and stations were rebuilt to allow the extended East London line to serve Highbury & Islington on fully segregated tracks
Double (volleyball) and indicates outstanding all-around individual performance. Quadruple-double is defined as an individual performance in which a player accumulates a double digit number total in four of the five major statistical categories--aces, kills, blocks, digs, and assists--during the course of one match. Because of specialization by position (setters, liberos, middle blockers, outside hitters, opposite hitters, defensive specialists, etc.), quadruple doubles are seldom seen at collegiate or professional levels. Quintuple-double is defined as an individual performance in which a player accumulates a double digit number total in all five statistical categories (aces, kills, blocks, digs, and assists) in a single match. Such