Subject
Bridges
Rivers
50
Historic buildings
22
Boats
19
Castles & palaces
19
Piers & wharves
17
Railroads
17
Ships
14
Harbors
13
Streets
11
Towers
8
Dwellings
7
Mountains
7
Railroad bridges
7
Valleys
7
Roads
5
Cliffs
4
Churches
3
Courthouses
3
Lakes & ponds
3
Railroad stations
3
Villages
3
Waterfalls
3
Barracks
2
Canals
2
Gardens
2
Hotels
2
Islands
2
Parks
2
Steamboats
2
Universities & colleges
2
Architecture
1
Beaches
1
Capes (Coasts)
1
Cathedrals
1
Meadows
1
Plazas
1
Round Towers
1
Ruins
1
Wetlands
1