I checked out the Klondike Gold Rush Museum, a free museum near Pioneer Square. The museum details the treacherous journey into Alaska, the process of staking a claim, and the wealth that the gold rush brought back to Seattle.
One prominent stampeder was John Nordstrom, who used his gold earnings to start a shoe store. The humble shoe store grew into the Nordstrom department store chain. Nordstrom is headquartered in Seattle.
The UPS Waterfall Garden Park is right by the museum. I found a geocache there.