I'll meet you at the subway station! This sign can usually be found in big cities and serves as a guide in local public transport. Because subways, outside of Germany usually called Metro, run underground. This sign indicates where a station is located.
The circled M emoji was introduced in 1995 and released as part of the Unicode 11.0 standard. This emoji can be found under the symbols
category. Because the circled M emoji has been around for quite some time, it should display correctly in the majority of operating systems.