Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Name | Built | Listed | Location | County |
| --- | --- | --- | --- | --- |
| B & O Railroad Potomac River Crossing | 1894, 1931 | 1978-02-14 | Harpers Ferry, West Virginia | Washington |
| B & O Bridge | ca.1867 | 1977-11-23 | Keedysville | Washington |
| Bennies Hill Road Bridge | ca.1889 | 1979-06-27 | Middletown | Frederick |
| Bloomington Viaduct | 1851, 1916 | 1976-11-21 | Bloomington | Garrett |
| Bollman Suspension and Trussed Bridge | 1869 | 1972-10-18 | Savage | Howard |
| Bullfrog Road Bridge | 1908 | 1978-11-21 | Taneytown | Carroll |
| Carrollton Viaduct | 1828, 1829 | 1971-11-11 | Baltimore | Baltimore City |
| Casselman's Bridge, National Road | 1813 | 1966-10-15 | Grantsville | Garrett |
| Crum Road Bridge | ca.1880 | 1978-12-28 | Walkersville | Frederick |
| Fourpoints Bridge | ca.1876 | 1978-11-29 | Emmitsburg | Frederick |
| Gilpin's Falls Covered Bridge | ca. 1855 | 2008-12-03 | North East | Cecil |
| Howard Street Tunnel | 1890, 1895 | 1973-07-02 | Baltimore | Baltimore City |
| Jericho Covered Bridge | 1865, 1937 | 1978-09-13 | Jerusalem , Kingsville | Baltimore , Harford |
| LeGore Bridge | 1898-1900 | 1978-09-18 | Woodsboro | Frederick |
| Lombard Street Bridge | 1877, 1974 | 1972-09-27 | Baltimore | Baltimore City |
| Loys Station Covered Bridge | ca.1860 | 1978-06-23 | Thurmont | Frederick |
| Old Mill Road Bridge | 1882 | 1979-03-07 | Rocky Ridge | Frederick |
| Patterson Viaduct Ruins | 1829 | 1976-06-03 | Catonsville , Ilchester | Baltimore , Howard |
| Poffenberger Road Bridge | 1878 | 1978-11-29 | Middletown | Frederick |
| Roddy Road Covered Bridge | ca.1860 | 1978-06-23 | Thurmont | Frederick |
| Thomas Viaduct, Baltimore & Ohio Railroad | 1835 | 1966-10-15 | Relay | Baltimore , Howard |
| Union Arch Bridge (Cabin John Aqueduct) | 1864 | 1973-02-28 | Cabin John | Mongtomery |
| Utica Covered Bridge | ca.1860 | 1978-06-23 | Thurmont | Frederick |
| Waverly Street Bridge | 1892 | 1984-09-07 | Westernport | Allegany |
| Wilson's Bridge | 1819 | 1982-03-15 | Hagerstown | Washington |
Question:
What is the County of Howard Street Tunnel?
Answer:
Baltimore City