。
We gazed steadily at the beautiful scenery.
Literal
We [topic-は] that beautiful scenery [object-を] steadily gazed.
じっと is a 擬態語 (state mimetic) for stillness and focused concentration — doing something steadily, unmovingly, with focus. 見つめる ('to gaze, stare') is transitive and inherently implies focused looking. Together, じっと見つめる intensifies the sense of quiet, absorbed gazing. A literary, sensorial moment.