Margaretta Township, Erie County, Ohio

The Blue Hole is a fresh water pond and cenote located in Castalia, Erie County, Ohio, in the United States. From the 1920s to 1990 the Blue Hole was a tourist site, attracting 165,000 visitors annually at the height of its popularity, partly because of its location on State Route 269, about 7 miles (11 km) southwest of the Cedar Point amusement park in Sandusky, Ohio. The Blue Hole was known to American Indians and was first recorded in history in 1761.The Blue Hole captured the public’s interest because of its size, about 75 feet (23 m) in diameter, clarity, vibrant blue hue, and enigmatic "bottomless" appearance. Contrary to prevalent belief, the depth of the Blue Hole is not unknown, but has been sounded and found to be about forty-three to forty-five feet (13.1 to 13.7 m) deep. Water temperature is about 48 °F (9 °C) throughout the year. Floods and droughts have no effect on temperature or water level. The Blue Hole is fed by a passing underground stream which discharges 7 million US gallons (26,000 m3; 5.8×10^6 imp gal) of water daily into Sandusky Bay to the north, feeding into Lake Erie. The water contains lime, soda, magnesia and iron, and because the Blue Hole is anoxic, it cannot naturally sustain fish. The surrounding terrain is developed on limestone bedrock and exhibits karst topography due to dissolution of the limestone by ground water, creating a cenote, a water-filled sinkhole. Several similar cenotes are known to local residents. The Blue Hole that once was a tourist attraction is now off limits to the public. It is located on the grounds of Castalia Trout Club, a privately owned fishing club. It is to be distinguished from another cenote, similar in size and eerie bluish-green color, owned by the Castalia State Fish Hatchery and operated by the Ohio Department of Natural Resources, Division of Wildlife, which is open for public viewing and which has grown in popularity since the closure of the Blue Hole in the late 1990s.

Castalia is a village in Erie County, Ohio, United States. The population was 774 at the 2020 census. It is part of the Sandusky, Ohio Metropolitan Statistical Area.

Margaretta High School is a public high school in Castalia, Ohio. It is the only high school in the Margaretta Local Schools district. They are members of the Sandusky Bay Conference.

Crystal Rock is an unincorporated community and census-designated place in Erie County, Ohio, United States. As of the 2010 census it had a population of 176. It is located within Margaretta Township.

Bay View is a village in Erie County, Ohio, United States. The population was 608 at the 2020 census. It is part of the Sandusky, Ohio Metropolitan Statistical Area. The village consists primarily of summer homes (many converted to year-round use) and a few small businesses. The community lies on the shores of the Sandusky Bay. The village was incorporated in 1951.

The Thomas A. Edison Memorial Bridge, otherwise known as the Edison Bridge, carries Ohio State Routes 2 and 269 over Sandusky Bay. The bridge, which is 2,049 feet (625 m) in length, was completed in 1965. It was named for inventor and nearby Milan native Thomas Edison.

Sandusky Bay is a bay on Lake Erie in northern Ohio, formed at the mouth of the Sandusky River. It was identified as Lac Sandouské on a 1718 French map, with early variations recorded that suggest the name was derived from Native American languages. The Thomas A. Edison Memorial Bridge was constructed across it in the 20th century to connect highways in Erie and Ottawa counties.

The Vacationland region of Ohio—billed as such for being known primarily as a major summertime tourist destination—is the area that is generally considered to be in the north central part of the state, and along the western half of the Lake Erie shoreline around Sandusky Bay, specifically the counties of Erie, Huron, Ottawa, and Sandusky.

No. 5 Fire Station in Sandusky, Ohio, was built in 1906. It was listed on the National Register of Historic Places in 1982.It was one of four fire stations built of cut limestone in Sandusky which held horse-drawn equipment. It is a two-story building with a hipped gable roof.

Holy Angels Church is the oldest extant church building in the Roman Catholic Diocese of Toledo and Erie County, Ohio. The stone Gothic Revival style church is located on West Jefferson Street at Tiffin Avenue and Clinton Street in Sandusky, Ohio. It was built in 1841 and added to the National Register of Historic Places in 1982.

Sandusky station is an Amtrak station in Sandusky, Ohio. Located at 1200 North Depot Street, the station consists of an uncovered platform on the north side of the east–west tracks, a small parking lot, and two buildings. The former Railway Express Agency/baggage building is boarded up, while the main building has a small, remodeled waiting room for Amtrak passengers as well as offices for the Sandusky Transit System and North Central EMS. The Sandusky station was originally built in 1892 by the Lake Shore and Michigan Southern Railway. It was designed by architects Shepley, Rutan & Coolidge and was also a work of A. Feick & Bros., and was listed on the National Register of Historic Places in 1975. In the heyday of passenger train travel in the first six decades of the 20th century the station was a local stop, bypassed by most New York Central named trains on the Chicago-New York City circuit. Exceptions were the Iroquois and the Chicagoan's eastbound trip. Additionally, the Cleveland-Detroit Cleveland Mercury made a stop at Sandusky. Passenger services ended in 1971, but were reinstated on July 29, 1979 when Amtrak added it as a stop on the Lake Shore Limited.The station is served by the Capitol Limited and Lake Shore Limited routes, both of which pass through Sandusky in the middle of the night. Because the station consists of only one platform, eastbound trains switch to the usual westbound tracks to pass the station.

The Engine House No. 1 in Sandusky, Ohio was built in 1915. It was listed on the National Register of Historic Places in 1982.It is a two-and-a-half-story limestone building. It has two square towers, at its northeast and southeast corners. It is Greco-Egyptian-Functional in style.