The same sights by public transport

By public transport the day costs €5 with TUSSAM's one day tourist card, or less if you pay per ride. Most visitors need only two or three rides, because the cathedral, the Alcázar and Santa Cruz are next to each other.

The T1 tram links Plaza Nueva, the Archivo de Indias, Puerta de Jerez and Prado de San Sebastián, which is 5 minutes from Plaza de España. Circular lines C1 and C2 go round the Isla de la Cartuja and the Macarena, and C3 and C4 follow the inner ring past Paseo de Colón and Plaza de Armas.

Metro line 1 crosses from Puerta de Jerez to Plaza de Cuba in Triana in one stop. Two adults save €46 on the day compared with two 24 hour bus tickets.

A Leap card does the same day for €6.00 at most. The Luas Red Line is the useful tram: from Abbey Street it stops at Smithfield for the Jameson Distillery, Museum for Collins Barracks, Heuston for Phoenix Park and James's for the Guinness Storehouse, a 7 minute walk.

Buses G1 and G2 run from Wellington Quay to Kilmainham Gaol, which the sightseeing bus leaves you 14 minutes short of. Bus 73 runs from Dame Street to James's Street for the Storehouse.

Each journey is €2.00 and the card stops charging after the third one. Two adults save €51 on the day compared with two Discover tickets.

A 24-hour BKK travelcard is 2,750 Ft, about €7.45. Tram 2 runs along the Pest embankment from Jászai Mari tér past Parliament (Kossuth Lajos tér), the Chain Bridge and Vigadó tér to Fővám tér, by the Great Market Hall, with the Castle in view the whole way.

Metro line M1 runs under Andrássy út from Vörösmarty tér to the Opera, Hősök tere and Széchenyi fürdő. Bus 16 goes from Deák Ferenc tér over the Chain Bridge up to Dísz tér in the Castle District, and trams 19 and 41 follow the Buda bank.

Those four lines reach, or come within a few minutes' walk of, all 10 sights on our list. The one place where the tourist bus is clearly easier is the Citadella.

By public transport the same day costs €5.35 with an Andante 24 for two zones, plus €0.60 for the card. STCP bus 500 leaves Praça da Liberdade and follows the Douro through Massarelos and Foz to Castelo do Queijo and Matosinhos, the same riverside stretch as the Red Line.

Metro line D crosses the top deck of the Dom Luís I Bridge from São Bento to Jardim do Morro in one stop. Bus 203 runs from Casa da Música metro to Serralves.

You get no commentary and no guaranteed seat upstairs. Two adults save about €44 on the day compared with two 24 hour bus tickets.

By public transport the same day costs €4.10. That is OASA's 24-hour ticket, or the daily cap if you tap the same bank card each time.

Metro line 2 stops at Akropoli for the Acropolis and its museum, at Syntagma for Parliament and at Omonia. Line 1 links Monastiraki and Thissio with Viktoria, 6 minutes' walk from the National Archaeological Museum.

The Panathenaic Stadium has no metro station, and the walk from Syntagma through the National Garden takes about 14 minutes. Two adults spend €8.20 for a day against €40 for two bus tickets, and the tram from Syntagma to the coast is included.

A day of Lothian buses and Edinburgh Trams costs £5.70 with TapTapCap: tap the same contactless card on each ride and charging stops at that amount. A single is £2.40.

Bus 35 runs along the Canongate and High Street between Holyrood and Chambers Street, which is the stretch of the Red Route that saves the most climbing. The tram goes from Princes Street to Ocean Terminal for Britannia, and buses 23 and 27 go from The Mound towards the Botanic Garden.

For two adults that is £11.40 against £44 on the sightseeing bus. What you give up is the commentary and the open deck.

A 24-hour Wiener Linien ticket is €9.70 in the app, so two adults pay €19.40 against €74 on the bus. Trams 1, 2, D and 71 run along the Ring past the Opera, the Hofburg, the museums, Parliament and the Rathaus.

No single tram does the full circle, so change between line 1 and line 2 at Schwedenplatz or at Oper/Karlsplatz. Tram D continues from the Ring to Schloss Belvedere and Hauptbahnhof.

The U4 goes from Karlsplatz to Schönbrunn in 6 stops, and the U1 from Stephansplatz to Praterstern in 3. Between them these lines reach every sight on the sightseeing bus map, at intervals of a few minutes instead of 20 to 30.

By public transport the same day costs £8.90 at most. That is the daily cap for Zones 1 and 2 when you tap the same contactless card or phone on every Tube and bus.

Stick to buses and the cap is £5.25, with single rides at £1.75. Bus 15 runs from Trafalgar Square past St Paul's Cathedral to the Tower of London, and bus 9 covers Trafalgar Square, Piccadilly, Hyde Park Corner and Kensington High Street.

Both are ordinary double-deckers where the front seats upstairs go to whoever gets there first. You get no commentary and the windows are closed.

Two adults save about £46 on the day compared with two One Day tickets.

The subway does the same day for $18 or less, at $3.00 a ride. The 1 train runs from Times Sq-42 St to WTC Cortlandt for the 9/11 Memorial and on to South Ferry for the Statue of Liberty boats.

The 4 and 5 trains run from Grand Central to Brooklyn Bridge-City Hall and Wall St. For a view from a seat, the M55 bus runs south down Fifth Avenue and Broadway from 44th Street to South Ferry for the same $3.00. The M4 bus goes up Madison Avenue to the Metropolitan Museum at 82nd Street.

Two adults save $88 on the day compared with two Discover tickets.

A 24-hour ATAC pass costs €8.50, so two adults pay €17 against €56.10 on the bus. Metro B runs Termini to Colosseo in two stops and on to Circo Massimo.

Metro A links Termini with Barberini, Spagna and Ottaviano, the station for the Vatican Museums. Buses 40 and 64 run from Termini through Piazza Venezia and Largo Argentina to the Vatican side of the river, which is close to the sightseeing bus's own line, and tram 8 goes from Piazza Venezia to Trastevere.

What you lose is the open top deck and the commentary. What you gain is a metro station at the Colosseum door, where the sightseeing bus currently has none.

A Navigo 1-Day Pass costs €12.30 and covers every metro, RER, bus and tram in zones 1 to 5. That is €26.70 less per adult than the 24-hour bus ticket.

Two regular bus lines do a similar sightseeing job for a €2.05 Bus-Tram ticket: bus 72 follows the right bank of the Seine past the Louvre and Concorde towards Trocadéro, and bus 69 runs from the Champ de Mars past Les Invalides and the Musée d'Orsay to the Louvre and on to the Marais and Bastille. Metro line 6 crosses the river on a viaduct at Bir-Hakeim with a clear view of the Eiffel Tower.

You get no commentary and no open top deck, and you have to work out the connections yourself.

A 24-hour Carris/Metro ticket is €7.25 plus €0.50 for the card. Tram 15E runs from Praça da Figueira and Praça do Comércio to the Mosteiro dos Jerónimos stop, and bus 714 does the same trip.

From the monastery it is about 1 km on flat ground to Belém Tower. Tram 28E links Graça, Portas do Sol, the cathedral, Baixa and Estrela, which is most of what the bus misses.

Bus 737 climbs from Praça da Figueira to the castle gate, and the metro Red line reaches Oriente for the Oceanarium. Two people pay €15.50 with cards included, against €44 for two 24h bus tickets.

What you give up is the commentary and a guaranteed seat: 28E is packed for most of the day.

The metro does most of this for a third of the price. ATM's daily fare is €7.60 and applies automatically from the fourth contactless journey on the same card, since four singles at €2.20 would come to €8.80.

Line M1 links the Duomo, Cairoli for the Castello, Cadorna and Conciliazione for the Last Supper. Line M2 goes to Porta Genova for the Navigli and M5 to San Siro Stadio.

Tram 16 runs above ground from the Duomo along Corso Magenta past Santa Maria delle Grazie to San Siro, and tram 1 passes La Scala, Cairoli and the Arco della Pace. Two adults save €29.80 on the day compared with two 24 hour bus tickets.

Public transport costs about a third as much and runs far more often. Contactless payment on STIB-MIVB is €2.40 a journey and stops charging at €8.50 a day.

Metro lines 1 and 5 link Gare Centrale with Parc, Schuman and Merode, which covers the Royal Quarter, the European Quarter and the Cinquantenaire. Trams 92 and 93 run along Rue Royale and Rue de la Régence past Place Royale, the Sablon and the Palais de Justice.

Metro line 6 goes direct from Rogier, Arts-Loi or Louise to Heysel for the Atomium. Two adults save €32.50 on the day compared with two 24 hour Tootbus tickets.

A Zone A Tourist Ticket costs €10.30 for one day, and with the 10-trip ticket at €7.30 six rides come to about €4.40. Metro line 2 strings together Ópera (Royal Palace), Sol, Banco de España (Cibeles, Prado, Thyssen) and Retiro.

Line 1 stops at Estación del Arte for the Reina Sofía, and line 10 at Santiago Bernabéu. EMT bus 27 runs the length of the Paseo del Prado, Recoletos and the Castellana from Atocha to Plaza de Castilla, which is the trunk of Route 2, and you see the same fountains and towers from a normal bus window.

The stretch where the tourist bus has no easy equivalent is the western loop from Moncloa down past the Teleférico and round below the palace.

Public transport is cheaper and gets closer to the sights. A GVB Day ticket costs €10 for 24 hours on all GVB trams, buses and metros, and bank card taps stop at €10.50 a day.

Tram 2 runs from Centraal Station through the centre to Leidseplein and the Rijksmuseum. Trams 13 and 17 go from Centraal Station to Westermarkt, next to the Anne Frank House.

Metro line 52 takes two stops from Centraal Station to Vijzelgracht, 3 minutes from the Heineken Experience. Two adults pay €20 for the day on GVB against €55 for two 24 hour bus tickets.

A Hola Barcelona card for 24 hours costs €11.25 online and covers metro, TMB buses, trams, the Montjuïc funicular and one airport metro trip each way. Metro L3 does much of the Blue Route's work: Catalunya, Passeig de Gràcia for Casa Batlló, Diagonal for La Pedrera, Lesseps for Park Güell and Palau Reial for Pedralbes and the Camp Nou.

L2 and L5 stop at Sagrada Família and L4 at Barceloneta. For Montjuïc, bus 150 leaves Plaça d'Espanya and climbs past the MNAC, the Olympic Stadium and the Fundació Miró to the castle.

Bus 24 from Passeig de Gràcia stops by the upper gate of Park Güell, which saves the climb the tourist bus leaves you with. What public transport does not give you is the commentary, the top-deck view and a seat for the whole loop.

By public transport the same day costs €10.10 for one adult, the MVV single-day ticket for zone M. Bus 100, the museum line, runs from the Hauptbahnhof past Königsplatz, the Pinakotheken, Odeonsplatz and the Haus der Kunst to the Ostbahnhof, close to the Green Tour's northern half. Tram 19 crosses the old town from Stachus past the National Theatre and along Maximilianstraße.

Tram 17 goes to Schloss Nymphenburg and the U3 to Olympiazentrum for the Olympiapark and BMW Welt. Two adults pay €19.70 with a group day ticket against €48.60 for two Express Tickets.

None of these has commentary or an open deck.

A BVG 24-hour ticket for zones AB costs €11.20, less than half the bus, and includes up to three children aged 6 to 14. Three public double-decker lines pass most of the same sights.

Bus 100 runs from Zoologischer Garten past the Victory Column, Schloss Bellevue, the Reichstag, the Brandenburg Gate, Unter den Linden and Museum Island to Alexanderplatz. Bus 200 links Zoo, Potsdamer Platz and Alexanderplatz.

Bus 300 goes from Potsdamer Platz along Unter den Linden and past Alexanderplatz to the East Side Gallery, which the Classic Tour misses. They run far more often than the sightseeing bus, but there is no commentary, the roof is closed and the front seats upstairs fill up fast.

Public transport does the hill part of this route for a fraction of the price. AT buses 12 and 13 run from Santa Maria Novella station to Piazzale Michelangelo in opposite directions around the same avenues, and a ride is €2.

Six rides in a day cost €12, and most visitors need two. Bus 7 goes from Piazza San Marco to Fiesole for the same €2.

Inside the centre there is nothing to ride: the main sights sit within 1.8 km of each other. What you give up is the open top deck and the commentary in 8 languages.