Peter Finch is perhaps the foremost chronicler of Cardiff, past and present. His response to the 2020 lockdown restrictions confining people to their local authority area was to begin walking the boundary of his. This was in a mirror of his long walk along the south Wales coast recorded in Edging the Estuary. The Cardiff border rarely appears on maps. The city is no longer has walls (like York or Chester), or a modern transport périphérique like London’s M25. Instead its dotted line boundary travels across fields, along motorways, up rivers, through forests, over rail tracks and along miles of intertidal mudflats following the edge of the Severn. The border itself is made up of waymarked trails, city streets, highway liminal zones, woodlands. Mud-soaked tracks up hillsides, bridges, diversions, disentanglements and discoveries all play a part in this informative text created for walkers and armchair travellers alike. Edging the City explores (often literally) why and where borders exist, their purposes, their love of water courses. It discusses other cities with walkable borders including York, Chester, London, Paris, Bruges and Seoul. It considers legal and geopolitical reasons for borders (the battles over placement of ‘Welcome’ signs, for instance), how they change and what happens when politics crosses boundaries. Cardiff’s medieval and other boundaries are tracked. The border is walked, run and sailed. Finch talks to ultra runners who have traversed the 50 plus mile route in a single day. He provides textual diversions on border history, north Cardiff trees, words for mounds, the mountains of Cardiff, the city’s coalmines, its triads, historical figures, battles, hill forts, poets, politicians, housing developments and other divertissements. There’s a city’s edge playlist which filled the author’s head as he strode available on Spotify. Edging the City is a view of Cardiff like no other, full of insights and discoveries.