In Baltimore, Mayor Stephanie Rawlings-Blake will attend ceremonies at City Hall shortly after New Year festivities at the Inner Harbor.
On Tilghman Island in the Chesapeake Bay, six couples will marry at the Black Walnut Point Inn on Tuesday. Owners and same-sex couple Bob Zuber and Tracy Stables will marry as well. Stables says the island community has been highly supportive.
Same-sex couples in Maryland have been able to get marriage licenses since Dec. 6, but they don't take effect until Tuesday.
Nine states and the District of Columbia have approved same-sex marriage. Maryland is the first state south of the Mason-Dixon Line to do so.