Opened in 2000, Big Oaks isn't a typical National Wildlife Refuge. It's located on the site of the U.S. Army's Jefferson Proving Ground, which was used for military training. So it's entirely possible to be exploring the 50,000-acre park and see an unexploded ordinance next to a beaver dam. Don't touch them (then again, after you watch the safety video before heading out, you've already heard that message).And Big Oaks isn't fancy. It doesn't have developed hiking trails, and its CCC-style building for private parties is beautiful but in need of some TLC. But it definitely is a worthwhile place to go fishing, to go bird-watching or to take a guided tour with zealous fish and wildlife specialists who are all too happy to get out of their cramped offices and show off their park. We saw snakes, deer, crawfish frogs and plenty of songbirds during our visit and would definitely go back for one of the special programs offered throughout the season, including a Becoming an Outdoors-Woman weekend. Just check the online calendar before you go. The refuge opens for the season in mid-April, and it is open to the public on Mondays, Fridays and the second and fourth Saturdays of the month.