O.K., folks. I am nervous about telling you this secret because, honestly, I want it all to myself. That said, the whole point of Yelp is to share or help - so here goes: There are dozens of FREE classical concerts throughout the year - during the week (and sometimes on the weekends) at the Library of Congress concert hall (below ground). They often feature the best string quartets in the world. You have to get tickets (through Ticketmaster), but it's FREE. Need I say more to you classical music fans out there? Get off your arses and go. They are fabulous. You will be hooked.
Pros: The reading room, the concerts, the mosaics
Cons: nada
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