15 interesting staircases but my favorite (at least for today) is this staircase at the SDM Apartment in Mumbai, Maharashtra, India; designed by Arquitectura en Movimiento Workshop (www.arqmov.com/en/). (Photo: Bharath Ramamrutham).

More pictures of this projects and 14 other staircases at:

Source: 15 Fantastic Photos of Stunning Staircases | ArchDaily