De 1949 à 1989, 456 tirs de bombes atomiques à uranium et à hydrogène sont effectués sur le site de Semipalatinsk. Certaines parties du polygone peuvent aujourd’hui être explorées sans danger. S’aventurer sans un guide expérimenté dans la zone reste néanmoins interdit.
https://www.lonelyplanet.fr/destinations/asie/kazakhstan/villes-et-regions/est-du-kazakhstan
Truly one of the most amazing places the interested and engaged world traveller can possibly visit, this remote and supremely dark place is deep in the steppe of Kazakhstan to the south-west of the semi-abandoned town of Kurchatov, where the bomb itself was designed, refined, and tested.
‘Polygon’ as a Russian language term just implies a place, so this Nuclear Polygon is the area where tests took place, 456 such tests took place, with weapons of various design, model, lethality, and blast radius.
Atmospheric tests (meaning above ground, since banned by international treaty), and underground tests, test using animals and machinery as subjects all took place here. Tests even more sinister than that are rumoured too.
Semipalatinsk Nuclear Test Site – The Polygon | Kazakhstan Travel Guide
https://koryogroup.com/travel-guide/semipalatinsk-nuclear-test-site-the-polygon-kazakhstan-travel-guide