Complex sentence: Solomons was a rather isolated boat-building town housing the University of Maryland Chesapeake Biological Research Laboratory, until 1970 when the Patuxent River Bridge was built to make the town more accessible.
Split into simpler sentences: Solomons was a rather isolated boat-building town housing the University of Md. Chesapeake biological research laboratory, until 1970 when a Patuxent River bridge was built, which made the town more accessible.