Panam Nagar is a single street in Sonargaon, the old capital of Bengal under the Sultans and Isa Khan's Bara Bhuiyans. In the 19th and early 20th centuries Hindu cotton merchants lined it with grand two- and three-storey houses, mixing European and Mughal styles.
Fifty-two of those buildings survive, many roofless and propped up, along with an old mint house and an East India Company indigo works nearby. The street is a protected site and has been ticketed since 2015.
It is a short auto-rickshaw ride from the Folk Art Museum, and the two make a full day from Dhaka. Don't climb on the buildings — several are unsafe.