Do your Irish ancestors come from Cavan? The Cavan Townlands website have recently uploaded a new dataset of census (and census substitute) records with a specific emphasis on the towns of County Cavan. They have created a homepage for each town where all the available 19th century records can be viewed in one location. The records include the 1821 census (covering the towns of 17 of the 36 parishes). Tithe Applotment Book records of c.1832 covering most towns of the county, 1841 census of the parish of Killashandra which covers the towns of Killashandra and Arvagh and Griffith's Valuation covering most of the towns. The 1901 and 1911 records will follow in due course.
An historical map of most towns with townland boundary overlays has been included to help in locating records. They have also compiled a list of population and number of houses for each town covering every decade from 1821 to 1911.
You can read the introduction, list of towns and guide to these records here: https://cavantownlands.com/towns-of-cavan/
This is a typical town homepage: https://cavantownlands.com/virginia-town/