We were there in 1946. Russia in those years had extensive documentation on Nazi technology; some even many German scientists were taken to Soviet lands to collaborate in the country’s arms growth.
Kapustin Yar was an excellent location. A desolate region 100 kilometers from Stalingrad (modern-day Volvograd). Stalin sought, above all, to feed on all of Nazi Germany’s knowledge, thereby building a very powerful infrastructure thanks to German advances during the war. Kasputin Yar would then be a top-secret military base. And progress was not long in coming.