Sylvester Park is a historic city park in downtown Olympia, Washington listed on the National Register of Historic Places. It was donated for public use by Edmund Sylvester in 1850 and was later under the jurisdiction of the state government from 1905 to 1955. Between , the park was known as Capitol Plaza.
Edmund Sylvester donated the land (block 16 on the city's original plat) for public use to the city in 1850. The lot remained undeveloped for several years before being cleared and fortified with a blockhouse.
During the Puget Sound War, the park was occupied by Olympia residents fleeing the conflict. In 1855, William White was killed by Wa-Le-Hut (Yelm Jim) which alarmed several hundred residents. Sometime in October-November, a high blockade was built along 4th Avenue (now Legion Way SE), bay-to-bay with a gate at Main Street, a cannon and nightly armed patrols secured residents, expecting to shelter north of the blockade; however, no attack actually took place.
In 1893, a year after the Old Capitol Building across the street was completed, the park was officially landscaped with a Victorian bandstand, a pond stocked with fish, maple and beech trees, and clamshell-surfaced walking paths. The park block was surrounded with a decorative iron fence.
On May 22, 1903, President Theodore Roosevelt delivered a 40 minute speech to a crowd of thousands at the park.
The bandstand was demolished in 1928 and the pond was filled in some time after World War II.
In 1955, the legislature passed an act to retract Olympia's proprietary rights to the park, to build an underground parking garage on the site. The city enacted a protective ordinance to preserve the park through a vote the same year.
The current gazebo was constructed in 1975 and is approximately in size.
The park contains several historic markers: