Md. Code, Courts and Judicial Proceedings § 3–203

(a) An initial petition shall be filed with the court in the county:

(1) As provided by the agreement; or

(2) Where the arbitration hearing was held.

(b) If the agreement does not provide for a county in which the petition shall be filed or if the hearing has not been held, the petition shall be filed with the court in:

(1) The county where the adverse party resides;

(2) The county where the adverse party has a place of business; or

(3) If the adverse party has neither a residence nor a place of business in the State, any county.

(c) A subsequent petition shall be filed with the court hearing the initial petition unless the court directs otherwise.