Venice to Ljubljana

Probably the train from Venice Mestre to Trieste and then bus from there to Ljubljana.

On your way back, you can change trains at Mestre to the Frecce train to Florence. Total travel time from Trieste to Florence is 4 hours 15 minutes.

The FlixBus takes 1.5 hours between Trieste and Ljubljana. There may be others as well.

There is direct FlixBus service between Venice and Ljubljana now. There's also a well-regarded Slovenian transfer company called GoOpti that offers shared transfers (a van) at a good price if booked in advance. There's also a "bus company" called DRD that I've used a few times - and even though they've been OK for me, I wouldn't recommend them anymore based on other feedback I've read about them.

Direct train service is supposed to resume between Ljubljana and Trieste this year (has already been pushed back a few times). So, if that happens before your trip, you'd be able to train between Ljubljana and Venice with a change in Trieste. You might be able to get a direct train from Trieste back to Florence (so maybe a bus from Ljubljana to Trieste, which I did last year; the bus and train stations in Trieste are adjacent).

We (4 of us) are going one-way from Venice to Ljubljana on Sunday, September 30th. We will be taking the train to Trieste in the morning (07:41-09:46), spending time doing a little site-seeing (including lunch) before we take a GoOpti "Private Car" (whatever that may mean) to Ljubljana. Our GoOpti reservation is at 3:00 PM and is expected to arrive in Ljubljana by 4:30 PM. Total cost for the 4 of us is €92. For the convenience we found that quite reasonable. Best wishes with whatever you may choose.

I am planning to use GoOpti from Venice (Piazza Roma) to Ljubljana. Around 30 Euros per person on the dates I’m looking at. As others have said, there is also the train from Venice to Trieste and from Trieste to Ljubljana. I am not sure the Trieste - Ljub service has started; it is new.

Beth, look at FlixBus too - would be a lot cheaper than GoOpti most likely, if there is a bus that works. I hear GoOpti is great and might be a tad faster (and for a little extra cost could drop you right at your hotel instead of just at the train or bus station). Ljubljana is however very compact and walkable. I never have trouble walking from the train/bus station to my lodgings in town, but I have always stayed in the northern part of the town (the train/bus station is in the northern part).

You can still get between Venice and Ljubljana by train via Trieste even if the new service isn't yet running, if you don't mind a little creative detour between Trieste Centrale and the train station at Villa Opicina. The easiest thing to do would be to take a taxi. There's an old tram that is currently not running I believe; a bus runs in its place but doesn't get you right to Villa Opicina. (I looked at this connection last year.) Of course, you can just take the bus from Trieste to Ljubljana. This option makes more sense if you would like to stop for a few hours in Trieste en route.

Another recommendation for GoOpti. We took this shuttle yesterday from Venice to Ljubljana. It was a comfortable 2.5 hour ride that we shared with a delightful Slovenian family. We had purchased our tickets about 10 months ago and it was € 52 with 2 suitcases. The driver was right on time and very kind. They email you the day before with pick up time. Great customer service!

I had an easy and very affordable GoOpti trip between my hotel in Ljubljana and Piazzale Roma in Venice, in June 2018. Easy to book on-line and the trip was probably just about 3 hours long, including one 15-minute bathroom break at a highway rest stop. With your itinerary, I'd suggest first booking GoOpti between Piazzale Roma (in Venice, assuming you are staying in Venice proper and not on the mainland; the vaporetto stops there, and it is the end point for buses and cars entering Venice) and your hotel address in Ljubljana. For your return, book from your Ljubljana hotel to the train station in Venice Mestre. From Mestre, as noted, you'll easily be able to take the fast train to Florence. This combination would give you both the fastest method between locations, but also the least amount of distance having to haul your bags around. One thought: you will probably want to pre-book your train tickets to Florence, to get better prices. HOWEVER, you'll want to look at how much more you will need to pay GoOpti to have an absolutely assured pick-up time. (With GoOpti, the more flexible you are with pick-up time, the cheaper the cost of the transport.) I'd give yourself a good four hours between time of leaving Ljubljana and your train tickets from Mestre to Florence; there is sometimes a lot of traffic on the highway in the final stretch between Trieste and Venice.