Orchard Rd is walkable, at least allowing plenty of breaks in air-conditioned shopping centers. You can no longer cross the central Orchard/Scotts intersection on foot: instead, take the air-conditioned underground walkway system that links Orchard MRT/Ion Orchard to Wisma Atria, Ngee Ann City and Lucky Plaza east, to CK Tang/Marriott north, and to Shaw House and Wheelock Place west.
