The double-decker is perhaps the GOAT of London icons — especially the vintage RT types and Routemasters. Since the first original Routemaster retired from London routes in 2005 though, it's tricker to thumb a ride on these pillar box red buses. But where there's a will there's a way. Here's how to ride on a vintage bus in and around London.
Hop aboard the T15

As of 2021, the days of swiping in on a number 15 heritage bus with your Oyster/contactless are over. But the route — running between Waterloo station and Tower Gateway, along the Strand and Fleet Street — now operates as a weekend service, the T15. It's £7.50 for an adult day ticket (a conductor checks tickets and shouts the stops), which isn't all that bad if you're a retro bus nut who wants to see London in style. Family and group tickets are available too. The Londoner Bus Company also run tours of London on vintage buses.
Look out for London Bus Museum heritage route days

We'll readily forgive the London Bus Museum for technically being outside the boundaries of Greater London, not least because they organise semi-regular vintage bus days that run through London itself — and don't charge a fare, either. Look out for these heritage bus rides along routes including the 19 between Finsbury Park and Battersea Bridge; the 418 between Epsom and Kingston; and the 54 between Woolwich and Elmers End. Learn/relive the joy of a hop-on platform, and maybe even get an old school ticket issued by a conductor.
Go on a vintage sightseeing bus

A panoply of vintage sightseeing experiences ply the streets of central London, and while they're a good deal more expensive than the T15, they do offer a eclectic range of experiences, good for special occasions. Here are some to know about:
📷 Ride over Tower Bridge and pause at Buckingham Palace for snaps on London City Bus Tours' open top vintage bus.
👻 Surely the niftiest-named tourist attraction around, Ghost Bus Tours bids you to board a funereal-looking service — a Routemaster-meets-the-Munster Koach, if you will — and tune into blood-curdling stories about the city's horrific past.
🎭 Ham it up on a Classic Tour open top bus, where 'Lord Larksworth' and 'Cheeksworth' will show you all the spiffing sights, in a kind of 'West End on wheels' do.
🍰 Dig into a dine on board sightseeing service; these include tea and cake courtesy of Brigit's Bakery and the English Tea Bus, plus porcine fun for kids with the Peppa Pig Afternoon Tea Bus. There are also experiences which end with fish and chips in a pub, although as all Londoners know, it's better from a chippie sitting on a park bench, shooing away pigeons.
Get married/invited to a wedding

It's almost as common these days to see a brace of newlyweds shuttled to their reception in an old Routemaster as it is in a classic car. A number of old Routemasters, RT Types et al rattle through the city of a Saturday — the ribbons and 'Wedding Special' destination boards being the giveaway that any old tourist can't just flag one of these babies down. Among the companies you can charter from are Routemaster Bus London, London Retro Bus Hire, Vintage Red Bus Company and Go Ahead. They're available for non-nuptial events too.
Catch the shuttle to the Epping Ongar line

You'd be forgiven for thinking the Epping-Ongar Railway was all about the trains, but in fact the first experience for passengers arriving at Epping Tube station is to be picked up by a vintage bus, and pootled over to the station at North Weald a few miles away. Sometimes, more vintage buses are on show outside here too. And at the end of a hard day's heritage train to-ing and fro-ing, it's back on the bus, destination: 21st century.
Do the whole Imberbus thing

Outside of London — but a popular annual day trip nonetheless — Imberbus offers the uncanny chance to charge around Salisbury Plain in various vintage Routemasters. This magical event, which takes place one Saturday every August, is the result of a tipsy conversation in a Bath pub in 2009 — to which we say: more power to tipsy pub conversations!
Stationary buses

This article's specifically about vintage buses that move, although there are plenty of stationary services you can climb aboard, including a double-decker you can drink on in the beer garden of the Old Bank of England pub on Fleet Street, and a parked-up bus at Wood Green's Blue House Yard, which'll ply you with Cornish pasties and comedy.
Feature image: Clive A Brown via creative commons