At the western edge of Karaoglanoglu (Karaoğlanoğlu), the coastal corridor transitions toward the Alsancak direction where a roundabout regulates flow distribution. The exposure forms not inside the roundabout, but in the approach phase.
The critical window appears between 17:00–19:00 on weekdays and 12:00–14:00 on summer weekends.
The corridor leading toward the roundabout is visually straight and relatively open. Drivers maintain steady coastal rhythm for several hundred meters before the circular junction becomes fully dominant in the field of view.
The risk is delayed deceleration.
Because the roundabout is visible from distance, drivers subconsciously postpone braking. The structure is seen early, but behavioural adjustment begins late.
A recurring scenario unfolds during late afternoon westbound flow. A vehicle approaches the Alsancak-bound roundabout at consistent corridor speed. Ahead, another driver has already begun reducing speed in anticipation of circulating traffic within the roundabout.
The following driver recognizes the slowdown slightly later than optimal. Braking pressure increases more sharply than necessary. Behind them, spacing compresses in sequence.
The geometry contributes subtly. The roundabout sits beyond a segment that still feels like uninterrupted coastal road. There is no abrupt narrowing, incline change, or surface shift to signal immediate behavioural transition. The mind reads continuation; the infrastructure requires modulation.
Summer intensifies the pattern. Increased density toward Alsancak beaches and residential zones elevates entry hesitation inside the roundabout itself. Vehicles within the circle may pause longer than expected while judging entry gaps. This hesitation propagates backward into the approach lane.
Even in winter, commuter return traffic creates steady westbound rhythm that is disrupted when roundabout entry speed is not recalibrated early enough.
Lighting conditions add variability. In late afternoon, west-facing light reduces contrast between carriageway and roundabout island edge. The structure remains visible, but depth perception compresses slightly. Drivers interpret distance as longer than it is.
Historically, before traffic density along the Karaoglanoglu–Alsancak axis increased in the 2000s, approach speeds were lower due to lighter overall flow. As corridor usage intensified, rhythm stabilized at higher average speed, making deceleration timing more critical.
The risk is not aggressive driving. It is perceptual delay.
As long as the coastal corridor maintains open visual alignment directly into a controlled circular junction without strong physical speed-calming thresholds, roundabout speed reduction delay will remain a recurring exposure at the Alsancak approach from Karaoglanoglu.