Which preposition to use with sanatorium

in Occurrences 2%

I left the sanatorium in March, 1901, and remained for three months in the home of this kindly fellow, who lived with a grandmother and an aunt in Wallingford, a town not far from New Haven.

at Occurrences 1%

Reluctantly permission was given by the Pope, and Ippolito, after the completion of his diplomatic duties in Naples, sought the neighbourhood of his innamorata; ostensibly upon the plea that his health needed the rest and change which the invigorating air of the Foresteria, a sanatorium at Itri, offered.

by Occurrences 1%

VII Choice of a sanatorium by people of limited means is, unfortunately, very restricted.

of Occurrences 1%

The father had left the Sanatorium of the South Dublin Union on hearing of the mother's delicacy.

Which preposition to use with  sanatorium