Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) said that the Prophet (peace and blessings be upon him) said: "The whole earth is a mosque except the graveyard and the bathhouse."
(b) Sayyiduna Ibn Umar (may Allah be pleased with them both) said that the Prophet (peace and blessings be upon him) said: "Pray in your houses, and do not make them graveyards."
(c) Sayyidah Aishah and Sayyiduna Ibn Abbas (may Allah be pleased with them) said that the Prophet (peace and blessings be upon him) said: "The curse of Allah be upon the Jews and the Christians; they took the graves of their prophets as places of prostration." He was warning against doing what they did.
(d) It is reported from Sayyiduna Abdullah bin Amr bin al-As (may Allah be pleased with them both) that he disliked a man praying in the bathhouse.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4275