Site visited in early 90ties and revisited shortly after inscription (July 2019).

I must say I really like this place. Comparing to Spiennes it is better preserved and much more interesting. It is also well maintained and prepared for mass tourism. All that applies to main component (Krzemionki Opatowskie) - area located between villages Sudół and Magonie (coordinates 50.971817, 21.491227). It is a place where former Krzemionki village was located, now it is only museum and archeological reserve of former flint mining.

At first glance it may not be very spectacular. These only visible remnants of mining activities are just small mounds or holes in the forest. But the real treasure lies under the ground. This is fully preserved flint mine from Neolthic period including corridors cut in the limestone and chambers. As far as I know it is the only one in world (those at Spiennes are just individual shatfs not connected each to another). The main reason for its preservation was lack of human settlement in the area after the place was abandoned in early Bronze Age (around 1600 BC).

Some practicalities as of July, 2019: visit of archeological reserve and museum is possible only with a guide. Fees are not big comparing to other monuments (18 / 12 PLN normal discounted, which is approximately 4,25 / 2,8 EUR), the whole trip takes around one hour and includes 500 m underground walk. Be prepared to take some warm clothes with you as these galleries are below 10 meters below ground level. The groups could be up to 30 people (in fact in summer months, especially in weekend there are big number of people). My last visit was on Saturday 10.00 - 11.00 a.m and the group were around 30 people, previous and next were similar.

The best way to get there is by car - 8 kilometers north-east of Ostrowiec Świętokrzyski (the main town in the area). There are also intercity buses (Polish PKS Ostrowiec Świetokrzyski) - any of them going to Lipsk or Solec nad Wisłą, get off at bus stop SUDÓŁ/ 754 (KRZEMIONKI)/ 08. Timetable here.

From Ostrowiec Świętokrzyski it is also possible to take private TransKatrina bus # 110, timetable:

https://trans-katrina.pl/lista-przystankow/linia/110/

If it is necessary to stay overnight in the area - the best place is probably Bałtów (around 7 km from Krzemionki), where there are several farm accommodations for tourists or Ostrowiec Świętokrzyski with its hotels.

Official website of the mine (in english): http://krzemionki.pl/en/

Other inscribed places seem to be unprepared for tourism. I tried to visit Gawroniec part, coordinates 50°53'02.7"N 21°31'57.5"E but the area is inaccessible (no roads, private plots surrounding the place, no information). Maybe the place will be managed after inscription.