From Wiktionary, the free dictionary
Formed from кла́да (kláda, “pile”) + -ня (-nja).
кла́дня • (kládnja) f
- pile, stack of wood/coal/hay intended to start bonfire
- Synonym: копе́н (kopén)
- “кладня”, in Речник на българския език [Dictionary of the Bulgarian Language] (in Bulgarian), Sofia: Bulgarian Academy of Sciences, 2014
- “кладня”, in Речник на българския език [Dictionary of the Bulgarian Language] (in Bulgarian), Chitanka, 2010