Note: "中国文化之夜由美国子午线国际中心和中国驻美国大使馆联合举办。子午线国际中心是美国国务院开展公共外交、文化外交的一个非赢利公共外交机构。"
(a) "Happy Spring Festival - Chinese Culture Night"
(b) Meridian International Center https://en.wikipedia.org/wiki/Meridian_International_Center
(is headquartered in the historic Meridian House [address: 1630 Crescent Place NW, Washington, DC] and White-Meyer House [1624 Crescent Place])
NW stands for Northwest.
The two buildings (1624 and 1630) are next to each other. Indeed the address of Meridian International Center is "1624 - 1630 Crescent Place, NW Washington, DC."
(c) Meridian House. Meridian International Center, undated www.meridian.org/meridian-house/
shows photos that are more beautiful than the one in Wikipedia (which looks shabby):