it was added to the city's list of historic landmarks), the Mason's are reconsidering. Castalia. Virgil Hillyer, the first headmaster of the Calvert School, built Castalia between 1928 and 1929. It was named after the spring at the foot of Mount Parnassas in Italy that is said to have been inspiration for the muses. The prominent Baltimore architect Francis Hall Fowler was the principal architect of the Italian-inspired house. It was proposed for demolition in 2006 by the Calvert School, who hoped to construct an outdoor amphitheater in its place. The Baltimore Heritage filed a successful nomination for the building to be added to the city's historic landmark list, and the building was saved. 400 block of West Baltimore Street. This was the location of the first toll booth on the National Road. The block, across from the iconic Hippodrome Theater, is a mostly intact street wall of historic properties and includes two of the last nine full cast iron fronted buildings still standing in Baltimore. After plans called for the demolition of much of the south side of the block that were abandoned in 2009, the block has seen significant rehabilitation of its historic structures. Baltimore Heritage removed the block from the Historic Preservation Watch list in July 2010 in recognition of the substantial rehabilitation and renovation that has signaled a commitment to retain the historic buildings in this important part of the west side of downtown. Current preservation priorities Clifton Park Valve House. Built in 1887–1888, it was used to build machinery used in the operation of Lake Clifton, once a major part of the city's water supply and was connected to Lake Montebello to the north by a 108-inch underground pipe. Lake Clifton began to be filled and developed in 1962, and the Valve House was no longer needed and eventually abandoned. By 1971, the building was in a serious state of disrepair. Baltimore City owns the building, and recent plans for private restoration have failed. Eastern Female High School. This former school has been a landmark since 1976, and was declared one of Baltimore's "architectural gems" in a March 8, 2002 Baltimore Sun editorial. This structure is the city's oldest surviving purpose-built public school building. It was renovated and converted to apartments in the 1970s, but is currently owned by Sojourner-Douglass College, and has been vacant since 2004. Old Town Mall, Old Town. The 500 block