[Cincinatus' Wife]

The National Zoo never charges for entry.

[tanknetter]

The National Zoo never charges for entry.

True, but they mask their attendance revenue stream by charging for parking.

Smithsonian Air & Space Dulles does exactly the same thing: $15 per car.

[FreedomPoster]

Ah, mea culpa, but it is understandable that I thought so given the line in the article.

Clearly they need to charge admission.