above aerial-balloon angled angles apartment-blocks architecture backgrounds balloon below buildings cityscape colors colours condominiums flats flight-operation gondola height helium helium-balloon high high-rise modern motion movement multi-storey multi-story perspectives roofing roofs rooftops rooves safe safety scene scenery scenic secure secured shape shapes sights sightseeing Singapore skyline streets traffic views accommodation architectural-elements balconies balcony business city-scapes city-views commerce concrete contemporary contrast costly curved distance distant edges elements expensive exterior external glass hazy heights light linear lines recessed skyscrapers surfaces towering towers tree walls wealth windows appearances architectural box-like city contrasting holidays hotel hotels surface tourism tourists