Zip lining in Peñarrubia

This is the only zip line on earth that crosses an international border: the Limite Zero line launches from the Spanish side of the Guadiana river and delivers you, seconds later, into Portugal on the far bank — and because the two countries sit in different time zones, you effectively arrive an hour before you left.

The ride itself is a fast, exhilarating glide of several hundred metres high above the green river that divides the two nations, between the whitewashed border villages of Sanlúcar de Guadiana and Alcoutim.

It's a short, pure hit of fun rather than a full day out, but the novelty is genuine — a zip line that is also a frontier crossing — and it pairs perfectly with a lazy river-valley trip: a boat back across the water, lunch on one bank, a wander through the other.

Easy, cheap and quietly unique.

A single, fast zip-line ride of several hundred metres, launching from a tower on the Spanish bank of the Guadiana and landing across the river in Portugal — a genuine international, cross-time-zone crossing in under a minute.

It needs no skill or fitness: you're clipped into a harness, given a short safety briefing, and released to glide high above the river. The thrill is brief but real, with a great view down the green border valley and the two whitewashed villages on either bank.

It's a quick experience rather than a day out, easily combined with a boat trip back across the Guadiana and lunch in one of the two villages.

Turn up at the Limite Zero base on the Spanish side, at Sanlúcar de Guadiana, where you book the ride, get harnessed and briefed — no experience or booking marathon needed, though reserving ahead in busy periods helps. It runs year-round in daylight, weather permitting.

There are weight limits (a minimum and maximum) and a minimum age, so check before travelling. Bring your passport or ID as a keepsake of the border crossing (the countries share the EU, so no formalities), closed shoes, and sun protection.

Afterwards, take the small ferry back across the Guadiana and enjoy both riverside villages. It's cheap and quick, so pair it with a day in the valley.