The Guadiana is Spain's quiet river, wide and slow, and at Mérida it has been tamed since Roman times. The label on this stop speaks of a dam, and there is a low weir across the river here, just beside the old bridge and the Moorish Alcazaba, but the thing that really commands attention is the Roman bridge itself. It is about 790 metres long and carried by some sixty arches, one of the longest ancient bridges still standing anywhere, and for two thousand years it carried the road toward the north and west across this very stretch of water.
The bridge was built in the late first century BC, when the colony was new, and it has been rebuilt and patched many times since. Floods have broken arches, wars have damaged piers, and in the 1990s it was closed to traffic and made a pedestrian walkway. The granite blocks are weathered and sometimes uneven, and walking across gives a feel for how the Romans placed everything with a view to permanent use. Downstream, the water spreads into shallows that attract egrets, herons and storks, and the evening sky over the river can be a vivid orange. The Alcazaba beside the bridge was built in 835 by Abd al-Rahman II, and a cistern inside reaches down to the level of the river.
For riders, the riverside promenade is a good spot to stretch after the road, with benches, shade and a long view. Mérida is a town of about fifty-six thousand, so fuel is easy, and cafés and bars are never far. The ride begins here and heads east toward Guadalupe, with straight, quiet roads across the plain before the road begins to climb. Heat is an issue in summer, and from midday the sun reflects off stone and tarmac with real force.
Pack a hat if you plan to wander, and carry water. Early morning is the nicest time to see the river, when mist sometimes lies on the surface and the bridge looks like a long, low line of arches floating in the light.