In 1916 which countries had western front trenches?

In 1916, the primary countries involved in the western front trenches were France, the United Kingdom, and Germany. The western front was characterized by a series of entrenched positions running from the North Sea to the Swiss border, where these nations faced off in brutal trench warfare. Notably, the Battle of the Somme, one of the largest battles of World War I, took place during this year, exemplifying the harsh conditions and stalemate on the front.