Which was John Denver's only solo UK number one single?

"Annie's Song" (also known as "Annie's Song (You Fill Up My Senses)") is a folk rock and country song recorded and written by singer-songwriter John Denver. The song was released as a single from Denver's album Back Home Again. It was his second number-one song in the United States, occupying that spot for two weeks in July 1974. "Annie's Song" also went to number one on the Easy Listening chart. Billboard ranked it as the No. 25 song for 1974.

It went to number one in the United Kingdom, where it was Denver's only major hit single (many of Denver's American hits were more familiar in the UK through cover versions by other artists). Four years later, an instrumental version also became flutist James Galway's only major British hit.