We'd find a section of hiking trail that'd need fixing, and bring in several weeks of food and supplies for 20 people on pack mules and set up a base camp somewhere.
From there, an average day would consist of us waking up at 5am, doing camp chores and some early morning PT, then breakfast. Then we'd hike an average of 15 to 20 miles a day, working sections of trails with picks, shovels, mattocks and Pulaskis (various tools).
That would happen for 8 hours a day with a 30 min lunch break and two 15 minute breaks. It paid about $8 an hour. We'd work typically for two week sprints (we called them spikes) without access to showers or electricity. Water was carried or pumped from rivers, and sometimes the whole crew would come down with some water borne illness from all the cow poop runoff in the rivers. We'd wear the same two uniforms for those two weeks, drenched in sweat and dirt every day, until our next town run half a month later.
Most days we'd just be digging dirt, but some days we'd also move multi ton rocks with giant crowbars or cut down dead and dangerous trees with long crosscut saws wielded by two people. Occasionally we'd build staircases out of rock, or crush boulders to make a French drain for a swampy area.
It was by far the hardest thing I've ever done, before or since. It was also one of the best times of my life.