Wikipedia
Siwki is a village in the administrative district of Gmina Grabowo, within Kolno County, Podlaskie Voivodeship, in north-eastern Poland. It lies approximately east of Kolno and north-west of the regional capital Białystok.
The village has a population of 130.
Siwki or Siwek (literally Easter Greys, as in grey horses) is a regional tradition rooted in Polish folklore, in which a procession of dressed up individuals stops passers-by and performs tricks on them. The event usually takes place on Easter Sunday or Easter Monday.
The map of Polish Easter processions devised by Andrzej Brencz demonstrates that similar processions take place in areas where villages are close to each other. The area where the Easter Greys tradition is observed stretches between Międzychód, Wolsztyn and Poznań in Poland's region of Greater Poland. The Greys are an example of immaterial cultural heritage of the region.