My employer granted me a one-year sabbatical in 2016. As a result, my resume currently looks like this:
Foo Widget Corp, Senior Engineer, January 2014 -- February 2016, February 2017 -- Present
In my cover letter, I explain that I took a year's sabbatical and spent it backpacking across three continents. I'm also quite happy to talk about it in interviews because it was a great experience and I learned a lot.
Someone recently suggested to me that I might want to include a brief explanation on my resume itself for the gap, since "nobody reads cover letters." While I fully accept that nobody reads the letter -- I've been involved in hiring senior engineers at Foo Corp the entire time I was there, and I've never seen a cover letter -- I don't think that it's necessary to include in the resume itself because it detracts from all the other things I'm trying to say about my experience in the position (responsibilities, accomplishments, etc.)
The other questions I've found about "explaining away" an employment gap all seem to be about gaps for negative reasons. Others, like this one talk about using the cover letter to excuse a gap pre-emptively. However I already am using the cover letter to explain that this was a sabbatical, and I did certain cool things which gave me certain cool skills/taught me useful things that I've applied upon my return; my concern is about putting something in the resume itself. This question indicates I should be attempting to explain somewhere but doesn't clarify if the cover letter is sufficient.
Should I indicate that my employment gap was due to a sabbatical granted by my employer on the resume itself, or is it sufficient to mention it in the cover letter and interview? If it matters, my field is software engineering (the title is actually 'senior software engineer', not just senior engineer) and the country is the United States.