Found Keys near Witzschdorf, Zschopau, Germany

Found multiple keys on a keyring. One key has a blue plastic cap with 'ABUS ZY02494', another is a 'BKS' key, one key has a custom smiley face cutout, and a set of keys is attached to a yellow plastic tag handwritten with 'Bamberg 3 2. OG Links'. Found on the Witzschdorf hill on a bench.