495号州际公路（Interstate 495，简称“I-495”），是美国州际公路系统的一部分，该条公路于1958年正式成为州际公路，全长64哩（约为103公里），是95号州际公路的一条辅助线。因为该条公路环绕美国首都“华盛顿哥伦比亚特区”，所以又被普遍称为“首都环线”（Capital Beltway），简称“环线”。除了首都华盛顿特区外，该州际公路还从与华盛顿特区比邻的马里兰州和弗吉尼亚州境内穿过。

Interstate 495 (I-495) is a 64-mile (103 km) Interstate Highway that surrounds Washington, D.C., the capital of the United States of America, and the city's inner suburbs in adjacent Maryland and Virginia. I-495 is widely known as the Capital Beltway, the DC Beltway or simply the Beltway, especially when the context of Washington, D.C., is clear. It is the basis of the phrase "Inside the Beltway," used when referring to issues dealing with American government and politics. I-95 utilizes the southern and eastern half of the Capital Beltway to circumnavigate Washington, D.C., and is cosigned with I-495 along that route.