John H. Ahern

John Henry Ahern (9 July 1903 – 24 December 1961) was a British model railway enthusiast, photographer and writer.

He is considered a pioneer of scenic model railways and one of the first to place a model railway within a landscape. The magazine Railway Modeller described Ahern's impact on the hobby as "fundamental and far-reaching". His 4mm layout, Madder Valley, built in the 1930s is preserved at the Pendon Museum in Oxfordshire.

Ahern was also an avid photographer alongside his wife Gladys. In 1932 he was elected a fellow of the Royal Photographic Society.