Shock statistics reveal that Burnley has the second highest rate of deaths relating to heroin and morphine misuse in the UK.
Figures released by the Office for National Statistics show there were 7.6 heroin and/or morphine related deaths per 100,000 people in 2016.
Burnley is second only to Blackpool which had the highest death rate with 14 drugs deaths per 100,000 people.
This compares with national averages of 1.7 in England and 2.3 in Wales
More than half of the heroin and morphine death hotspots in England and Wales are seaside locations, figures show.
Six of the 10 towns and cities with the highest rates of fatalities related to the substances are coastal holiday resorts, according to the Office for National Statistics.
A spokesman said: "Some of our best-loved holiday areas in England and Wales have become hotspots of heroin/morphine misuse deaths.
"Places that may have been more synonymous with family holidays are among the 10 areas that saw the highest rates of drugs misuse fatalities where heroin and/or morphine were mentioned on the death certificate."
Other seaside locations to feature in the 10 areas with the highest rate of heroin or morphine misuse deaths are Bournemouth, Portsmouth, Hastings, Thanet and Swansea.
Burnley, Reading, Hyndburn and Neath, Port Talbot complete the list.
The fortunes of towns such as Blackpool, Portsmouth and Hastings have been in decline since traditional coastal holidays fell out of favour in the 1960s, with the advent of package holidays abroad, the ONS has said.
It also pointed out that some of the 10 areas have high levels of deprivation, which could link to increased drug use.
A report from Public Health England published last year said: "Social factors, including housing, employment and deprivation, are associated with substance misuse and these social factors moderate drug treatment outcomes."
In 2016, analysis by the Advisory Council on the Misuse of Drugs concluded that a probable cause of recent increases in drug-related deaths is the existence of a prematurely ageing cohort of people who have been using heroin since the 1980s and 1990s.
Experts also identified a "deepening of socio-economic deprivation since the financial crisis of 2008" as a possible factor.
There were 3,744 drug poisoning deaths, involving both legal and illegal drugs, registered in 2016 in England and Wales.
This was up by 70, or 2%, on 2015, and the highest number since comparable data started in 1993.
The ONS report referred to the "Trainspotting Generation", which became addicted to heroin in the 1980s and 1990s, as a possible explanation for why the highest rate of death from drugs misuse was among 40 to 49-year-olds in 2016.