@BlueDan 5 July 2021 more from that month

Castle of Queen Maria of Romania in Balchik, Bulgaria. This castle, which is more of a holiday villa, was the Queen's summer residence between the two world wars when this region of Bulgaria (South Dobrogea) belonged to the Kingdom of Romania. Now, this castle is a museum and the surrounding gardens form a beautiful botanical garden, with the largest collection of cacti in southeastern Europe.