 The staggered structures incorporate two reinforced narrow islands.The upper island is traversed by and accessible by the lock gates or Teddington Lock Footbridge.The greater lock is against the general south (right, towpath or Surrey) bank of the river which is for 500 m north-east here; a middle lock being that most regularly used spans a long thin island which has lawns, places for boat owners to sit and a lock keeper's cabin and short thin island which is a thin wedge of concrete and a broad canoe/kayak stepped portage facility.