For old maps http://www.lancashire.gov.uk/ -> enter mario in the search box -> Maps and related information on line -> post code (LA3 3HD for the centre of Overton). The OS First edition 1:10,560 mapping for Lancashire was one of the first surveys undertaken by the Ordnance Survey. The 'original' maps were surveyed in the mid-1840s and published in the late-1840s. A 'revised' version was also produced in the 1860s 

 1930's map of Overton and a diagram of the Ship Hotel and Pedder Farm from; A Farming Year in the 1930's by Edward Baxter.