The majority of the borough is Metropolitan Green Belt, including nearly all of the land south of the A232-A21 route between West Wickham and Pratt's Bottom.

[3] Most of the population lives in the north and west of the borough, with an outlier at Biggin Hill in the far south.

Westerham Heights, the highest point in London and Kent at an altitude of 804 feet (245 m), is on the southern boundary.

Penge Urban District was the only part of the new borough which had been within the boundaries of the London County Council and Metropolitan Board of Works, voting to leave in 1899 to become self-governing until 1965.

The built-up area around Orpington not only encompasses its direct outskirts of Chelsfield, Crofton, Derry Downs, Goddington, Kevingtown, and Petts Wood; it also includes the erstwhile separate settlements of Farnborough, Green Street Green, Pratt's Bottom, St Mary Cray and St Paul's Cray.

In addition, parts of Mottingham, Sydenham, Swanley and Ruxley lie within the borough boundaries.

Biggin Hill, Downe and Keston with Leaves Green and Nash are separate, smaller, rural settlements.

Local attractions include Down House (the home of Charles Darwin), Chislehurst Caves, Holwood House (the home of William Pitt the Younger), Crofton Roman Villa, and the site of The Crystal Palace.

Since 2000, for elections to the London Assembly, the borough forms part of the Bexley and Bromley constituency.

However, the borough has many railway stations served by London Overground, Thameslink, Southeastern and Southern.

Stations operated by London Overground (all are also served by Southern): National Rail stations: Tramlink stops: In March 2011, the main forms of transport that residents used to travel to work were: driving a car or van, 27.4% of all residents aged 16–74; train, 5.1%; bus, minibus or coach, 5.1%; on foot, 4.3%; work mainly at or from home, 4.0%; underground, metro, light rail, tram, 2.3%; passenger in a car or van, 1.5%.

Beckenham, Bromley and Biggin Hill cover the rest of the borough with four pumping appliances and a hose layer.

Noticeably, compared to 2005/2006 there was an 11% decrease in special service calls (road traffic collisions, chemical incidents, flooding etc.).