I didn't see any mistakes in your journal entry (^_^) You could write "I went to a hot spring today, about an hour's drive away." Usually we would just say "I went to a hot spring today. It was about an hour's drive away."
今日、車で一時間ぐらいの温泉に行ってきました。
I went to a hot spring today. It takes an hour by car.
(← How can I make these sentence into one sentence?)
その温泉には岩盤浴もあり、楽しい時間を過ごせました。
There was a bedrock bath and
You could write "I went to a hot spring today, about an hour's drive away."
Usually we would just say "I went to a hot spring today. It was about an hour's drive away."