As ever this is just a fact finding thing, and probably won't come to fruition, however, I'm looking into the viability of picking up a couple of WHS on a stop over in Indonesia.

What is feasible in Bali in terms of visiting the WHS during a c.20 hour airport wait (not even sure if I could get out of the airport at this stage). The Royal Water Temple Pura Taman Ayun is the closest to the airport, but can you actually visit it, or just look at it from outside? I must admit I haven't got a full grip on the basics of the Subak system yet so any pointers, no matter how entry level would be welcome.

What would be a feasible amount of time to give to a stop in Yogyakarta, to enable a visit to Borobodur and Prambanan? (two days one night?) Is Yogyakarta itself worthy of more exploration. I'm also writing off Sangiran Early Man Site as a visit only if we end up with time to kill, is that fair or is it particularly impressive?

Jakarta, I see it is on the t-list and will probably have to go through it in transit anyway, is it worthy of a stay or just a place to go through if I'm short on time.

Like I said, this may not come to anything, but it is always useful to have a repository of information.

I was in Indonesia last year. Re Bali: mx experience is that you can't enter the inner sacred precinct of any major Balinese Temple (such as Besakih or Taman Ayun) but you can walk around the surrounding area (which in the case of Taman Ayun is part of the whs) and take pics from there. Fron Yogyakarta, you probably need a day for Borobudur and prambanan each (though maybe that was just how our tour was structured) - both are fairly close to Yogyakarta, but don't underestimate how long any trip in Java takes. Yogyakarta itself has the sultans palace and the Taman Sari water castle, both of which are nice but not absolutely unmissable. Jakarta is an exhausting metropolis - the old Batavia part is not very well preserved overall (apart from some individual monuments) and really not too spectacular.

I haven't been to Indonesia although I researched quite a bit about its WHS for a possible trip in the future. From what I've read and seen in photos, I would spend at least 2 days 1 night to visit Borobodur alone so as to visit at leisure and at different times of the day. Prambanan seems much smaller but I'd be against visiting both sites in 1 day.

Re the Royal Water Temple Pura Taman Ayun, apparently you cannot go in (except the nearby garden) so a guide would help appreciate the site for at least 1 hr. Again, if possible try to visit the site alone and not as a stop on the way to rice terraces and other sites.

I've been to Yogyakarta,
- Prambanan is an easy half day-trip from there (took me 50 minutes to get there by TransYogya minibus).
- For Borobudur I'd plan a full day for a day trip from Yogya. I hired a car and driver. It isn't such a vast site such as Angkor or Machu Picchu (it came 'only' 36 on our Top 200)
- Yogya town (mostly the palace indeed) could be seen on the other half of the day you've left after Prambanan. It's not a very cosy city, although it is reportedly one of Indonesia's most pleasant.
- I also did a day trip to Solo and Sangiran from Yogya, by train (and taxi for the last bit to Sangiran). Solo has a similar palace to Yogya, and is a nice smaller city.

If you really want, you can combine both Borobudur and Prambanan in the same day by hire a car with driver. Leave early morning to avoid the heat at Borobodur, or stay in hotel there for a sunrise and back to Yogyakarta to eat Suharti's fried chicken for late lunch and go to Prambanan around 3 PM to see the site and be there until twilight, visit Candi Sewu before Prambanan. I actually visit both sites in 2 days tour and found out this one day possibility.

At Yokyakarta, you can try Javanese food like fried chicken, Gudeg or Jackfruit stew both local style and royal style made from coconut flower in the palace, its local cake called bakpia and many interesting food.

Another choice is from Jakarta, buy one day tour to Krakatoa Volcano, and see Kota Tua, Jakarta Historic area before its evaluation in 2017!

Thanks for all that feedback, really handy, and has also made me pretty hungry.

I hadn't noticed that Jakarta was up for consideration next year.

Jakarta Old Town:
if you want to visit and see the whole thing, including the harbour, it could take longer than half a day.
The centre of the Old Town is packed in 1 place. Several museums, the quarter, etc. 3 hrs is enough. Yet should you wish to visit almost all sites, give yourself a full day. Starting from the centre of the Old Town, walk to each site, up to the harbour, then go back to the centre for late afternoon/sunset tea time in Café Batavia. A good restaurant that give you a sense of old town, over looking the plaza/quarter.
It gets really crowded during Saturday evening.

Jogjakarta:
as mentioned by Durian, Prambanan is closer to town. Borobudur should be a bit further.
Give a 2 days for the visit, you could see and visit other interesting sites and taste some local delicacy. You could see some sites that are used to be in the tentative list (yet not anymore)... The royal palace... The Ratu Boko Temple..
One could easily spend 3-4 days in that city and still longing for more. Guaranteed :-)
THEN,
you can have around 2 hrs drive to the city of Solo, to visit Sangiran Early Man Site. Book yourself a car for that. Yet I have to remind you that not very much to see there. Just a small museum (to my standard), and you need a good guide to take you to several places on foot (should the roads are too narrow), and explains things to you so you 'get it'. Half a day is enough. I went there just to give a tick on my list.

Bali:
Many sites that are covered in the WHS. You cannot visit all in 1 day due to distance etc. One is preferred to have a rented car (with driver) to get from one place to another.
Taman Ayun is quite in the center, so it's quite easy.
Lake Batur is quite up. Takes half a day to get there and back.
Rice Terrace along the area of Pakerisan Valley (Kintamani district) is worth seeing while going to the recommended Gunung Kawi Temple (part of the inscribed area). My personal favourite. You actually climb down to see the temple area (instead of climbing up).
So, should you have only 1 day lay over, Taman Ayun seems to be a better choice. If not, give yourself 3 days and enjoy it, with the local pace.

Hope this help.

The respected journal "Nature" has just just (Nov 6 2018) published a paper titled "Palaeolithic cave art in Borneo" which reports "a large reddish-orange figurative painting of an animal at Lubang Jeriji Saléh—a limestone cave in East Kalimantan, Indonesian Borneo—yielded a minimum date of 40 ka, which to our knowledge is currently the oldest date for figurative artwork from anywhere in the world."
https://www.nature.com/articles/s41586-018-0679-9
Assuming that the "science" is correct (and "Nature" is a prestigious journal with strict peer reviews) then this is comfortably "older" than e.g Chauvet!!

This is currently being "onward reported" by numerous daily newspapers etc around the World.
WHS travellers might be interested to note that the site of the Lubang Jeriji Saleh in East Kalimantan is in the area of Indonesia's T List site of "Sangkulirang – Mangkalihat Karts: Prehistoric rock art area" (sic - It should of course be "Karst"!! See https://en.wikipedia.org/wiki/Sangkulirang-Mangkalihat_Karst ) - http://whc.unesco.org/en/tentativelists/6009
The UNESCO entry contains a rather nice run down of the relative ages of a wide range of cave art sites from around the World - many of which are already inscribed! It was added in 2015 and the UNESCO description does not, of course, include this latest discovery - indeed the Cave remains are only a part of the wider claimed OUV.

I note also that the "second oldest" figurative art in the world (37900 YBP) is from Sulawesi and that this area too is on Indonesia's T List - "Prehistoric Cave Sites in Maros-Pangkep" - http://whc.unesco.org/en/tentativelists/5467
That dating only seems to have been made quite recently - c 2014 - and at that time made the claim to be the world's oldest!!
https://www.sciencemag.org/news/2014/10/indonesian-cave-art-may-be-worlds-oldest

Whether Indonesia will attempt to gain inscription for either of these T List sites is another matter!! They aren't exactly going to generate a lot of revenue!! Unless of course France would like to give them a very large amount of money to build a replica or 2 which could be sited in Jakarta I guess! But 3 of the 6 sites added to Indonesia's T List in 2015 are being progressed for nomination in 2019/20 and 21 according to our "information" - so, it is possible that Sangkulirang – Mangkalihat could "fit in" behind them. But the "Cave Art" domain has been getting a lot of attention recently with Chauvet (2014) and the German Ice Age Caves (2018) and can we really have a "race" by which any cave claiming greater age for its art work gets nominated?? It seems to be generally accepted now that "human art" goes back a lot further than was previously thought and also that it either occurred independently across human populations outside the most famous known sites in Europe or was taken to all these places by predecessors - so, with the latest techniques for dating art based on establishing the age of deposits under and over the art (thus permitting art based on ochre and scratching etc to be dated rather than only that which was charcoal based), we can expect more, and probably even earlier, examples to be discovered.

I wonder what Clyde must be thinking now, after his visit to Anak Krakatau a few months ago.

Just been viewing the dreadful scenes there.

I saw on Instagram that our own Bernard Joseph Esposo Guerrero was on a boat going past just a few days ago. He is safe and sound though.

My thoughts are mixed between being sad for the people of indonesia who really had a dreadful year in 2018 with all sorts of natural disasters on the one hand, and feeling even more lucky and priviliged to have been to such a place which is still in the making or still evolving. My pumice souvenir has truly became my most prized whs memento after the credencial and compostela.

Komodo National Park Shut Down for 1 Year

https://en.tempo.co/read/1166472/komodo-national-park-shut-down-for-1-year

Not quite, PLANNED to be shut down for one year. So far this is still only talk but sounds more serious than the high entrance fee report last year.

This sounds like it will happen for sure: https://www.thejakartapost.com/travel/2019/03/29/komodo-island-to-be-closed-in-january-2020.html