Country diary: The air is rich with post-dawn birdsong | Jennifer Jones

Halewood Park Triangle, Liverpool: Formed by train lines past and present, this suburban spot is rich with natureEarly on a calm May morning I am in a triangle: an isosceles triangle to be precise, with two equal sides and a shorter base. This is Halewood Park Triangle, south Merseyside: a wedgeland. The Triangle was forged by 19th-century developments in the railways, its base marking the main Liverpool-Manchester line, while the east and west arms were branch lines carrying passengers and frei