Azam Mosque:

Azam mosque of Qom is located next to the Holy shrine of Hadrat Masoumeh (s.) on the western side this mosque is made by Hussain Ebn Muhammad known is Lorzadeh with the effort of Ayyatullah Brujerdi.
This mosque is known as Azam (great) & that is because of it largeness, and it has three verandas. One large portico, are tall dome, one big veranda, two forty pillars, a library and some other rooms.

Old Jame Mosque:

This mosque is one of the oldest and biggest mosques of Qom and it is located in Talaqani Street. It is made in L.H 752 or 755, old Jame mosque includes a tall dome, a veranda, three bed - chambers a big courtyard, and one basement.

Emam Hasan Asquri (a.s.) Mosque:

It is known as Emam mosque, and it is located at the beginning of Astaneh street next to Alilikhani Bridge and it is near the Holy shrine of Hadrat Mosoumeh (s.) and it is one of an old and a creditable mosque of Qom.
Emam Hasan Asqari (a.s.) ordered to make the first building of Mosque and it was constructed by Ahmad Ebn Eshaq Ashari the representative of Emam Hasan Asqari(s.) in the third century and it was reconstructed & developed in safavi dynasty Emam mosque has four bed - chambers, one veranda, and one basement. Many religious school students study & discuss here.
Some other historical mosques of Qom are kohneh square mosque panjAli mosque, EshqAli mosque.

Source: Qom Cultural Heritage and Tourism Organization