Enabled by Deutschlandticket (€49/month unlimited local/regional transit in Germany) & the Italia In Tour ticket (€29/3days unlimited Trenitalia regional trains), I'm planning to spend the next few days traveling from Berlin to Southern Italy entirely on local & regional trains.
I furthermore intend to include urban metro systems wherever feasible/wherever they cross my regional-train path twice; accordingly my journey begins at the U-Bahn platforms of Berlin Alexanderplatz.
Train 1: U2 Berlin Alexanderplatz - Berlin Zoologischer Garten
Depart: 08:43 Arrive: 09:06
Frequency: Every 5 minutes
Operator: BVG (Berliner Verkehrsbetriebe)
Line opened: 1902-1913
Train 2: RE7 Berlin Zoologischer Garten - Dessau Hbf
Depart: 09:20 Arrive: 10:53
Frequency: Every hour
Operator: DB Regio Nordost
Line opened: 1877-1923, electrified 1992
Train 3: RB13 Dessau Hbf - Leipzig Hbf
Depart: 11:11 Arrive: 11:56
Frequency: Every hour
Operator: DB Regio Südost
Line opened: 1857-1859, electrified 1911-1921
Train 4: RE42 Leipzig Hbf - Fürth Hbf
Depart: 12:09 Arrive: 16:11
Frequency: Every 2 hours (supplemented by slower hourly trains)
Operator: DB Regio Bayern
Line opened: 1844-1885, electrified 1939-1942, DDR section de-electrified 1946, re-electrified 1964-1995
Train 5: U1 Fürth Hbf - Nürnberg Hbf
Depart: 16:28 Arrive: 16:44
Frequency: Every 5 minutes
Operator: Verkehrs-Aktiengesellschaft Nürnberg
Line opened: 1835 (first railway in Germany), converted to electrified tramway 1927, converted to metro 1985
Train 6: RE1 Nürnberg Hbf - München Hbf
Depart: 17:10 Arrive: 18:54
Frequency: Every 2 hours
Operator: DB Regio Bayern
Line opened: 1870-2006, electrified 1960-2006
Met up with @Alon in München
Train 7: RE96 München Hbf - Lindau Insel
Depart: 19:54 Arrive: 22:16
Frequency: Every 2 hours (supplemented by slower hourly trains)
Operator: Go-Ahead Bayern
Line opened: 1853-1890, electrified 1968-2021
Train 8: REX1 Lindau Insel - Feldkirch
Depart: 07:55 Arrive: 08:42
Frequency: Every 30-60 minutes
Operator: Österreichische Bundesbahn
Line opened: 1872, electrified 1927-1954
Train 9: S2 Feldkirch - Schaan-Vaduz
Depart: 08:47 Arrive: 09:05
Frequency: Peak only, 11 trains per day
Operator: Österreichische Bundesbahn
Line opened: 1872, electrified 1926
The single-track railway across Liechtenstein is the main route for nonstop intercity Switzerland-Austria trains, so there's not much space for local trains. In 2020 Liechtenstein voters rejected https://vorarlberg.orf.at/stories/3064562/ a referendum to double-track it & expand service.
Verkehr: „Nein“ zum Ausbau der S-Bahn Liechtenstein

Die Liechtensteiner Bevölkerung hat sich am Sonntag bei einer Volksabstimmung gegen den Ausbau der S-Bahn in Liechtenstein entschieden. 62,3 Prozent (10.382 Stimmen) sagten Nein. Mobilitätslandesrat Johannes Rauch (Grüne) bedauert den Ausgang.

ORF.at
In addition to seeing how far I can get on regional trains, my goals for this trip include visiting the three European countries I haven't been to, so I'm getting off here to spend the next few hours in Liechtenstein.
There are no more trains from Schaan-Vaduz until late afternoon so I'll then walk to Sevelen in Switzerland to continue onward.
Train 10: S4 Sevelen - Sargans
Depart: 13:47 Arrive: 13:56
Frequency: Every hour
Operator: Schweizerische Südostbahn
Line opened: 1858, electrified 1927
Train 11: S12 Sargans - Landquart
Depart: 14:06 Arrive: 14:18
Frequency: Every 30 minutes
Operator: THURBO
Line opened: 1858, electrified 1927
This train has "stop request" buttons?
Train 12: RE Landquart - Sagliains
Depart: 14:50 Arrive: 15:52
Frequency: Every hour
Operator: Rhätische Bahn
Line opened: 1889-1999, electrified 1921-1999
Train 13: R Sagliains - Pontresina
Depart: 15:55 Arrive: 16:57
Frequency: Every hour
Operator: Rhätische Bahn
Line opened: 1903-1913, electrified 1913
Well shit. Any ideas?
(Mastodon can't handle image uploads on flaky connections, see Bluesky https://bsky.app/profile/lexande.bsky.social/post/3kafaaoanwg2d or Twitter https://twitter.com/threestationsq/status/1707067743076307343 for updates.)
lexande (@lexande.bsky.social)

The huddle waiting for the ersatzbus is large and contains Bernina Express passengers who apparently have priority over us.

Bluesky Social
A large huddle of people waited for an ersatzbus, some who had apparently been there hours, including Bernina Express passengers who had priority over us. A train at track 4 was signed for Poschiavo but the staff said they were uncertain whether it would in fact run. The "coming soon" and "does not exist" signs on top of the station building seemed emblematic of the situation. Suddenly it was announced that a train would board on track 3, and the bus huddle returned to the rail platforms.
Train 14: R (despite being coupled to Bernina Express carriages) Pontresina - Tirano?
Depart: 18:08? (actually 18:21) Arrive: ??:??
Frequency: Normally every hour, today only when all hope seems lost
Operator: Rhätische Bahn
Line opened: 1908-1910 (electrified from the start)
The passengers applauded when the train started moving, though uncertainty remained about whether it would reach Tirano in time to catch the last train to Milano.
Train 15: RE8 Tirano - Milano Centrale
Depart: 20:08 Arrive: 22:40
Frequency: Every hour
Operator: Trenord
Line opened: 1840-1902, electrified 1902-1939
We wound up with a zero-minute transfer in Tirano. I was the first of several runners to make it across but in the end everyone who seemed to be in any sort of hurry made it. Trenord departed two minutes late (wonder how they feel about being held due to delays in Switzerland).
Train 16: M3 Centrale FS - Crocetta
Depart: 23:01 Arrive: 23:09
Frequency: Every 9 minutes
Operator: Azienda Transporti Milanesi
Line opened: 1990
Train 17: M3 Crocetta - Rogoredo FS
Depart: 09:09 Arrive: 09:17
Frequency: Every 3-4 minutes
Operator: Azienda Transporti Milanesi
Line opened: 1990-1991
Train 18: RV Milano Rogoredo - Bologna Centrale
Depart: 09:32 Arrive: 12:10
Frequency: Every 2 hours
Operator: Trenitalia Tper
Line opened: 1859-1861, electrified 1938
Train 19: R Bologna Centrale - Rimini
Depart: 12:34 Arrive: 14:03
Frequency: Every hour
Operator: Trenitalia Tper
Line opened: 1861, electrified 1938
Taking a side trip to San Marino by bus, but I will return to Rimini station to continue my regional-trains-only trip tomorrow.
🚡
I also had occasion to ride Rimini's grade-separated trolleybus rapid transit system, Metromare.
Train 20: RV Rimini - Falconara Marittima
Depart: 08:03 Arrive: 09:05
Frequency: 20 per day (mostly hourly with gaps)
Operator: Trenitalia Tper
Line opened: 1861, electrified 1938
Train 21: RV Falconara Marittima - Roma Tiburtina
Depart: 09:14 Arrive: 12:48
Frequency: 5 per day
Operator: Trenitalia
Line opened: 1865-1866, electrified 1935
Looks like we're taking the high speed (direttissima) line between Orte and Roma, so the above should actually say "line opened 1865-1977".
Train 22: MB Tiburtina FS - Termini
Depart: 13:04 Arrive: 13:10
Frequency: Every 10 minutes
Operator: Azienda Tramvie e Autobus del Comune di Roma
Line opened: 1990
Train 23: R Roma Termini - Formia-Gaeta
Depart: 13:36 Arrive: 15:06
Frequency: Roughly hourly
Operator: Trenitalia
Line opened: 1927, electrified 1935
Train 24: R Formia-Gaeta - Villa Literno
Depart: 15:26 Arrive: 16:09
Frequency: 22 per day (mostly hourly with gaps)
Operator: Trenitalia
Line opened: 1927, electrified 1935
Train 25: R Villa Literno - Napoli Campi Flegrei
Depart: 16:15 Arrive: 16:45
Frequency: 20 per day (mostly hourly with gaps)
Operator: Trenitalia
Line opened: 1925-1927 (electrified from the start)
Interesting seat design