• 坂さか — slope / hill
• 急坂きゅうはん — steep slope
• 坂道さかみち — sloped road
• 上のぼり坂ざか — uphill slope
• 下くだり坂ざか — downhill slope

The character 坂 combines 土つち (earth) and 反はん (oppose/turn). It suggests ground that turns or rises — in other words, a slope. Common in place names, street names, and directions in Japan.

急坂きゅうはんを自転車じてんしゃで登のぼるのは大変たいへんです。
It's hard to go up a steep slope by bicycle.

この坂道さかみちは 秋あきに紅葉こうようが綺麗きれいです。
This hill is beautiful with autumn leaves.