Hartlepool is a post-industrial port town on the Durham coast, about 30 kilometres south of Sunderland. It's not a place most visitors to northeast England seek out, but it has a genuinely interesting historic waterfront and makes a reasonable half-day stop if you're exploring the region.
The main draw is the Historic Quay around Hartlepool Marina, with the National Museum of the Royal Navy and the HMS Trincomalee as its centrepiece — a 200-year-old Royal Navy frigate and the oldest British warship still afloat. The reconstructed Georgian seaport does the usual costumed-guide thing, but the ship itself is worth the visit.
Seaton Carew, at the southern end of Hartlepool's long sandy bay, is a traditional English seaside resort — windswept, faded at the edges, but with a decent beach and a bracing North Sea atmosphere. In summer it draws families from across County Durham.
The original medieval town on the Headland is the other half of Hartlepool and the half most visitors miss. St Hilda's Church and the Heugh Battery — where guns fired back at the German fleet in December 1914 — are both up there. The Victorian new town centre, by contrast, was heavily redeveloped in the 2000s and is now dominated by retail parks and chain stores.