The Sentinel Block (1905) is a good example of a c.1900 romantic revival style commercial building and is of interest as it illustrates the important position held by community newspapers in the late 19th and early 20th centuries. The Iowa Falls Sentinel was born as the Eldora Sentinel in 1857. When Marcus Woodruff relocated the newspaper to Iowa Falls in 1865, he had an eye on the future. Business in Iowa Falls was brisk, the population was growing, and the promise of continued growth strong. The year after Woodruff moved his paper, the town received rail transportation, a strong assurance to businessmen that growth would follow in Iowa Falls.

The Sentinel Block represents a departure from earlier commercial buildings in Iowa Falls. These had almost all been Italianate in design with decorative hoodmolds and heavy metal cornices. With the new century came a new interest in a simpler form. The Sentinel Block represents an early expression of this. The hoodmolds have been replaced by rectilinear brick panels, and the cornice consists entirely of brick patterning with a very plain stone cap. The crenellated parapet on the oriel may have been a reaction to the Queen Anne influence of the 1890's. The first floor and basement are occupied by businesses and are open to the public during business hours. The building is located at 702 Washington Ave.