Riverside walk in Ljubljana

Sorry that I can't help with the riverside loop in Ljubljana, but there are two tourist offices in the old town that are very helpful. The one right at the river seemed busier, so I usually went to the other one with my questions. There are some worthwhile art/ethnographic museums in the city, covered by the city card (I think 32 euros last year). The card also covers castle entry, a self-guided audio walking tour, and a variety of other sights. You should do the math to be sure the card would be worthwhile for you. I spent a lot of time just wandering.

The city card covers a short boat ride on the river, but that was disappointing because there was no narration--not even in Italian or Slovenian. I'd be sure of English-language narration before paying for a boat tour, because you can see a lot for free just by walking along the river. Another outdoor possibility is the cemetery mentioned in the tourist materials. I didn't get to that.

Vintgar and Bled are both worth the trip; you can walk all the way around Lake Bled as well as pay for a boat ride out to the little island. However, those boats head out only when they are full. Check details on getting to Vintgar; buses aren't terribly frequent. If you put together a small group of people from the Bled bus station (before they've bought tickets), you can probably negotiate a good deal for a trip to one of the many attractive destinations not far from Bled, including Lake Bohinj as well as Vintgar. Buses to Bled itself are fairly frequent, but there's often a van waiting near the station, trying to cajole folks into a shared ride back to the city. As far as I know, he's totally legit, but he likes to have a good number of people in the van before he leaves. I found taxis surprising affordable in Slovenia.

Both the Postojna Caves and the Skocjan Caves are interesting. Skocjan is less touristy. The admission fees are not inconsequential. I was able to reach Skocjan via public bus (there may also be a routing involving a train), but there was some walking involved. I last visited Postojna many years ago and am not up to date on the transportation options for it.

The Istrian coastal town of Piran is said to be very nice; I ran out of time before I managed to get there.

English is spoken widely and well in Slovenia, so you should have no trouble getting tips from locals you meet.

Brilliant, thanks for the suggestions. I reckon the city card will be worthwhile for me, I've checked the list of benefits and I reckon I could get value from it. Buses, bike hire, castle admission, etc
I love wandering, too - with an occasional refreshment stop, so am looking forward to exploring, for me, a brand new destination. Sounds morbid maybe, but I do like to wander around cemeteries, always wildlife present and photo opportunities to be had, so thanks for the tip!
I love architecture, too, so will be checking main churches, etc, including the big Serbian orthodox church with it's dazzling frescoes.
The @visitLjubljana twitter account have been incredibly helpful and I'll check out the tourist office on arrival.
Thanks once again :)

I love Slovenia - it is my favorite European country. We have walked along the river, but I didn't do a loop. Maybe you will be lucky and happy to be there when the antique market is happening - it is the best on I have ever seen. Bled and Vintgar are special, especially Vintgar. Asdie from what you have mentioned, I highly recommend a visit to Piran. A very special place. It never ceases to amaze me how you can come from the Alpine looking mountains, cross a ridge and then be in Mediterranean paradise in less than two hours.

Acraven and Emily have given you some very good pointers, I would just add that I am not sure about the riverside walk you are referring to, but I think the following 6km (or 3km one-way) walk from the Botanical Gardens via Spica, the Trnovo "beach", a little side excursion along the Gradascica river to the Trnovo Church, then back to the Ljubljanica river, past the old town all the way to Plečnik's Locks on the eastern end of the city centre will cover the most interesting part of the river: https://goo.gl/maps/jRMsWYHqesE2 As a local, I would opt for that one. If you wish, you can extend it further east into the residential Moste district and then head back to the Botanical Gardens along the Gruber Canal, but there is no path along some parts of the river there so you would have to resort to using side streets and it's not particularly scenic either.

Another walk to consider, or better yet hike, is Smarna Gora (Mount Saint Mary) on the northwestern outskirts of the city, a must for any Ljubljancan (local). It's a hill with a church, an inn and great views at the top and there are many paths ranging from easy to quite steep. Bus stop Tacenski Most is closest to the starting point. You can reach it from the city centre via line 8 or, on Sundays, 1B.

One other option is to walk along part of the Remembrance Trail (also known by its Slovenian acronym PST), it's a 30km path encircling Ljubljana, like for example the stretch from Koseze Pond around the backside of Tivoli hill to the Zoo. There are plenty of scenic walking options further afield, too.

And a side note - cemeteries in catholic countries are a bit different to the ones you're used to in the US. Expect Zale to be very "built-up", not really a wildlife refuge but more of an architectural sight, heavily influenced by Plecnik.

Wonderful responses from ACraven, Emily and Dejan, thank you all.
I'd already penciled in walks up and around Roznik Hill but Smarna Gora has now been added to my (ever-growing) list.
Normally over ten days, I'd have 2 or 3 separate bases, but due to medical issues, I need to stay in one place for the duration. Sounds like there's more than enough in and nearby the city to occupy my time (and my camera) without too many worries!

You'll be entranced by the architectural details. They're very proud of Plecnik. Most likely there's some tourist literature about related sights.