咫尺天涯

so close, yet worlds apart (idiom)

8 in. length unit of Zhou dynasty

very close / very near

one of the characters used to represent a musical note in gongche notation, 工尺譜|工尺谱[gong1 che3 pu3]

a Chinese foot / one-third of a meter / a ruler / a tape-measure / one of the three acupoints for measuring pulse in Chinese medicine / CL:支[zhi1],把[ba3]

day / sky / heaven

the other end of the world / a faraway place

border / horizon / shore