The heart of Donegal Town is dominated by this imposing castle on the banks of the River Eske—and it offers a fascinating glimpse into Ireland’s complex history. First built in the 15th century by the local Irish chieftain, Red Hugh O’Donnell, the castle became home to plantation-era Sir Basil Brooke in the 17th century, who added a Jacobean house to the original square tower. Now restored, the house’s interior is furnished with period-appropriate French tapestries and Persian rugs.