Two of the most impressive places in Washington don't require advance reservations. The Library of Congress and the Washington National Cathedral are architectural and artistic treasures.
The cathedral was dubbed at its creation a "House of Prayer for All People," and does indeed draw people from all over the world seeking comfort and reflection. Statues of George Washington and Abraham Lincoln make it clear that this is a place where church and state are welcome to coexist. With its murals, paintings, sculptures and statues, and, of course, millions of books and manuscripts, the Library of Congress is truly impressive. Even if you’re not a bookworm, the free docent-led tour is one of the best things going in the city.