EN4: 33 m clear of the highest tide in the London Bridge ledgers

The lowest postcode in EN4, EN4 8NX, stands 33 m above the highest tide in the London Bridge ledgers (5.41 m, 1 February 1953). The highest, EN4 0NH, stands 122 m above it.
- Ground at eight in ten of its postcodes: between 51 m and 95 m, measured from Ordnance Datum; the middle one stands at 68 m.
- None lies in the Environment Agency's Flood Zone 3 from the sea.
- Mostly in Barnet; partly in Enfield.