Cow Tower stands beside the River Wensum as an early example of a purpose-built English artillery blockhouse. Constructed around 1398-99, the brick tower protected a strategic point in Norwich's defences, its position beside the water explaining why this stretch of river mattered to the medieval city. The exterior is the focus of a visit because the interior is closed for safety reasons. Take time to look at the tower's form and read the interpretation before continuing along the river. Visitors particularly enjoy combining the monument with the Wensum Riverside Walk, a two-mile route through the city centre identified in the official visitor guidance. Flat paths make the outside relatively easy to reach, although parking is elsewhere in Norwich. The station and Riverside car parks provide a walking approach, with shops, cafes and toilets in the city. Dogs on leads are welcome.