Ruislip Common once had a hamlet called Park Hearne, with a number of half-​​timbered cottages that were lost when the valley was flooded by the Regent’s Canal Company to create Ruislip Reservoir in 1811. The reservoir was designed as a feeder for the Grand Junction Canal, but never performed its task very successfully. The canal company developed the reservoir as a lido in the mid-​​1930s.

Early plans for the devel­opment of the Ruislip Manor estate proposed building houses almost to the water’s edge, but negotiations with landowners King’s College saved most of Park Wood for the public in 1932. Four years later Copse Wood and Mad Bess Wood were also acquired. Ruislip’s first council houses were built shortly afterwards on Reservoir Road.

The main lido building was demolished in 1994, after a fire the previous year, and was replaced by a pub. In 1997 English Nature designated neigh­bouring Ruislip Woods a national nature reserve, the first in a metro­politan district.

A café and woodland centre have been built at Woody Bay, which also has a new station building. At the other end of the railway line, an overflow car park has been laid out to cope with the lido’s growing popularity.

With its verdant setting, sandy beach, refreshment facilities and excellent miniature railway, Ruislip Lido justi­fiably attracts thousands of locals in summer – but few visitors come from farther afield because the amenity is something of a ‘well-​​kept secret’.

Away from the lido on the west side of the common, Breakspear crematorium is the second largest in London and is run jointly by the boroughs of Harrow and Hillingdon.

Evidence of late Bronze Age occupation has been found at Ruislip Common. Poor’s Field was first recorded as common wasteland in 1295.