Lallybroch is built. This is mentioned in Chapter 27 of Outlander.
There are questions about this date, though; it is probably only the laying of the foundations. In Chapter 34 of Drums of Autumn it says 1716, the year Brian and Ellen move in, and their oldest son William is born. In the first Epilogue of A Breath of Snow and Ashes, Brianna says 1721 – that is the year of Jamie’s birth and has to be a continuity glitch.