The history here is genuinely fascinating, and it's one of those rare stories where a government project actually worked out pretty well.
Before 1915, the area was a natural tidal marsh along the San Francisco Bay shoreline. Then the Panama Pacific International Exposition rolled through, and as was the fashion of the era, nature got paved over in the name of progress. The Army turned it into an airfield — Crissy Field — which served military aviation through much of the 20th century.
Fast forward to the 1990s: the National Park Service undertook a massive restoration project to return the site to something resembling its original marsh habitat. And credit where it's due — they pulled it off. Today, Crissy Field is one of the most beloved public spaces in San Francisco, a genuine ecological success story with restored wetlands, native plant life, and some of the best Golden Gate Bridge views money can't buy (because it's free).
Now, we're usually the first to side-eye a federal agency spending big to undo what a previous federal agency spent big to build. There's an irony in the government restoring nature that the government destroyed in the first place. But the result speaks for itself: a public asset that San Franciscans actually use and love, maintained without the kind of bloated bureaucratic overhead that typically plagues city-level projects.
Sometimes the best thing government can do is get out of the way — even if "getting out of the way" means undoing its own prior work. Crissy Field is proof that restoration, done right, is worth the investment.

