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 architectural art-glass color coloration colored colour coloured commercial decoration decorative distinctive geometric geometrical glass-panes lighting multi-colored multicoloured panes rectangles rectangular reflections shadows shaped stained-glass sunlight sunshine window-frames window-panes aircraft anchored cable checks circular control controlled duty-pilot engineers fabric filled inspected inspections large limited mesh metal-cable metal-line monitored monitoring net passengers pilot piloted registered ride tethered tourists weather-limits wind-limits