These are some of the oldest structures in Lancaster County, according to the National Register of Historic Places, the official list of the nation's historic places worthy of preservation.

Related: Map of all the historic properties in Lancaster County and Pennsylvania

Authorized by the National Historic Preservation Act of 1966, the National Register of Historic Places is part of a national program to coordinate and support public and private efforts to identify, evaluate, and protect America's historic and archeological resources.

Hans Herr House: 1719

Hans Herr House

The Hans Herr House in Willow Street is a prime example of German architectural features such as the pitched roof, plank shutters and casement windows, fieldstone walls and chevron doors. It dates back to 1719.

Witmer's Tavern: 1725

Witmer's Tavern

Part of Witmer's Tavern on Old Philadelphia Pike in East Lampeter was built in 1725.

Ephrata Cloister: 1732

Ephrata Cloister

Ephrata Cloister represents many Germanic architectural features. It dates back to 1732.

Donegal Presbyterian Church: 1732

Donegal Presbyterian Church

Pictured above is the original sanctuary of the Donegal Presbyterian Church on Donegal Springs Road in East Donegal Township, which dates to 1732 and is still in use. At right is the Kerr Study House, which is used as the church's administrative offices. (Donegal Presbyterian Church)

Ressler's Mill: 1737

Ressler Miller

The Ressler Mill and House is a well-preserved and fully functional grist mill in Upper Leacock Township dating back to 1737.

Abbeville: 1756

The stately Abbeville mansion was built on Columbia Avenue in Lancaster Township in 1756.

Speedwell Forge Mansion: 1765

The Speedwell Forge Mansion in Elizabeth Township dates back to 1765.

Jasper Yeates House: 1765

A blacksmith named John Miller built this house in 1765. It is named for its best-known owner, Jasper Yeates, a judge and one of the richest men in town at that time.

Poole Forge: 1779

Historic Poole Forge in Caernarvon Township dates back to 1779.

Rock Ford: 1794

Rock Ford in Lancaster was Gen. Edward Hand's home. It dates back to 1794.