Washington D.C.

According to zoo officials, safety and security are big concerns.

Over 30% of runners will be debuting.

There were nearly 22,000 finishers taking part in near-perfect fall conditions.

Runners now have the option to transfer their bib to someone else.

He won back-to-back weekend races and broke one course record.

"Coach Mike" always seemed to find the time to help a runner, regardless of ability.

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