20 Pa.C.S. § 722: Venue of trust estates.

When a Pennsylvania court has jurisdiction of any trust, testamentary or inter vivos, except as otherwise provided by law, the venue for all purposes shall be in the county where at the time being is the situs of the trust. The situs of the trust shall remain in the county of the court which first assumed jurisdiction of the trust, unless and until such court shall order a change of situs under the provisions of this chapter.