Alicante is one of the most accessible Spanish city breaks from UK regional airports — Ryanair and easyJet operate from dozens of UK airports year-round, making it a genuinely convenient long-weekend destination. The city itself is more rewarding than its reputation as a Costa Blanca gateway suggests: the Santa Bárbara Castle above the city (the largest medieval castle in Spain, accessible by a lift carved through the rock) gives the most dramatic clifftop view on the Spanish Mediterranean coast, the Explanada de España promenade is one of the finest palm-lined seaside walks in the country, and the local tapas culture — particularly the arroz (rice dishes) and the seafood from the Alicante fish market — is excellent.
From virtually every UK airport it's 2–2.5 hours — Ryanair and easyJet from London, Manchester, Birmingham, Glasgow, Edinburgh, Bristol and dozens of regional airports. Alicante-Elche Airport is 12km from the centre (TRAM train, 25 minutes, €3.85 or bus C6, 35 minutes, €2). Go from March to November: the summers are hot (35°C+) but the beach life makes it tolerable. Spring and autumn are perfect. The Las Hogueras de San Juan festival (Midsummer bonfires, June 20–24) is the most spectacular local festival — enormous sculptural structures burned on the beaches at midnight.