Not sure if this will be interesting or useful to anyone, but I've been in Ljubljana for three days now. I think I crammed in a lot of activities:
The first day was fairly quiet (my flight arrived late afternoon). Getting from the airport to downtown with public transit was cheap and straightforward. I walked from downtown to Tivoli park, and wandered around for about an hour.
Yesterday, I went to Lake Bled. From the bus terminal (on the east side the lake), I started walking clockwise around the water. I took the boat to the church on the island (which was a bit touristy, but still fun). I hiked to three lookout points on the western side of the lake. This was tougher than I thought! It was quite steep at times, but the views were stunning. After, I ate a slice of the Bled cream cake (light and delicious), and paid a usurious price for some badly-needed water bottles.
Then I walked to Vintgar Gorge from the NW edge of Lake Bled. The walk there was pleasant, but nothing special. The trail through the gorge was enjoyable (the canyon was deep). It was a bit crowded in places. I walked back to Lake Bled through Zasip (this walk was more scenic, through pastoral lands, with the distant mountains visible). I ended the day visiting the castle, which also provided some great views. It was a fantastic day of being outdoors. My watch said I took more than 35,000 steps! I was exhausted by the time I was back in town.
Today, I went to the Škocjan Caves (a UNESCO world heritage site). I was debating between this one, and the Postojna Cave. From what I understand, the latter is a bit more touristy, but the Škocjan system is much larger (unfortunately no photographs are allowed). I took the bus to Divača and walked 3 km to the location. I was blown away by the size of the Škocjan cave system. Some of the chambers are more than 100 meters tall. The first section was dry, and the second had a large river roaring through it (with many small waterfalls). You can't help but admire the bravery of the initial explorers. After, I took a long (outdoor) trail back to the starting point (this passed by several more chambers and waterfalls). I got back to Divača with two minutes to spare before the train. I took another (almost) 25,000 steps today per my watch. The past two days have left me utterly exhausted, but I took a long nap after dinner.
I can't speak a word of Slovenian (aside from a few simple phrases I've picked up - "dober dan", "hvala", etc) but I've found it easy to get around town. Both of the day trips I've taken were done via public transit, with no issues.
I'm going to explore Ljubljana more thoroughly on Saturday and Sunday (before the BL and IM shows), and then I'm going to go to Piran on Monday. I'm glad I booked a few extra days in Ljubljana, there's been so much to do already.