Postcards
Old postcards can be a good way of finding out more about how things looked years ago, especially when compared with modern images.
These galleries give you some examples.
Palma de Mallorca 33 Plaza de Cort
82 Palma de Mallorca El Puerto
Palma (Mallorca) La Catedral Martorell 1955
PHOTO AWC TEI PALMA Car 30/33 Oct 17 1957
41 Palma de Mallorca Calle de Colon 1910
Palma de Mallorca - 97 La Glorieta y el Borne 1930
Palma (Mallorca) R 86 Paseo Sagrera Rotger
37 Palma de Mallorca - Barrio de Santa Catalina Foto Coll 1916
No 84 Palma de Mallorca - Paseo Sagrero 1916
Nr 2 Palma de Mallorca El Borne
Note the first post card in this gallery though, the black & white mine railway at Perguera. There is indeed a sea side village of this name about 20 km south west of Palma. And the postcard was catalogued as being 'from Mallorca'. But.. it's the 'wrong' Perguera. The rather cute mine railway was on the Spanish mainland, near Barcelona. See this and this for details. This is a good illustration of not believing everything one reads on the Internet!
There are many web sites which sell old postcards, but a few good starting places are: