There are certain places where you cannot implement the electronic locking system such as antique doors of protected buildings and monuments but this doesn't mean we cannot use locks for doors at such places. Here is the RFID lock cylinder from Salto Systems which can overcome the challenges faced with electronic locks.

This RFID lock cylinder works with numerous doors ranging from traditional antique doors to contemporary modern tubular steel doors. It works with several RFID formats and in case of an emergency situation can be opened from inside with Portable Programming Device or PPD. It has been designed for Europrofil and Swiss Round and is available in both RFID and iButton versions and also gives acoustic and visual indications. Since it is compatible with NFC it can be seamlessly opened with NFC enabled phones.