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: Generally cold but less crowded, with holiday displays around the White House and National Mall . Transportation & Navigation

: A highly popular site that often requires advanced timed-entry passes.

: Often very hot and humid, making outdoor sightseeing draining; plan for museum visits during peak afternoon heat.

: Home to the Hope Diamond and massive dinosaur exhibits.

: Monuments are open 24 hours a day and are beautifully lit at night, often with far fewer crowds than during the day.

: Most are free to the public. Top choices include:

: September to November offers crisp breezes and changing leaves, while March to May features the iconic National Cherry Blossom Festival .