The event sees National Lottery funded projects across the United Kingdom offer free entry and other special offers to thank it and players who raise £30m every week for good causes.
Community interest company Hartlepower is holding Greenbank 100 Years On comprising tours of the former mansion house which is now occupied by social enterprises, businesses and Hartlepower’s own voluntary sector development unit.
People just need to present a National Lottery ticket or scratchcard for free entry.
Peter Gowland, of Hartlepower, said: “We’re delighted to be taking part in The National Lottery Open Week this year.
“We’ve been fortunate to receive National Lottery funding, which has enabled us to establish a new Voluntary and Community Sector (VCS) unit to support Hartlepool’s charities, community groups and social enterprises.
“This is our way of saying thank you to everyone who has bought a National Lottery ticket, helped HartlePower on our journey and made a vital contribution to supporting good causes.”
The offer will run between Monday, March 21, and Thursday, March 24, with 30-minute tours taking place between 10am and 2.30pm followed by free refreshments.
Everyone who takes part will be entered into a free prize draw with the winner receiving £25 of National Lottery scratchcards.
Booking in advance is not required.