An electronic timepiece device allowing indicating the current legal time of the place where the device is located and astronomical information, the electronic timepiece device comprising: - an electronic processing unit provided with at least one processor configured so as to periodically: ∘ determine first geo-location parameters associated to the place where the electronic processing unit is located and second parameters concerning the current legal time legally associated to this place, ∘ and establish, according to the first and second determined parameters (11, 12), local horizontal coordinates of the Sun in this place from predetermined calculation rules stored in a memory of the electronic processing unit, the local horizontal coordinates comprising at least the azimuth of the Sun, - a dial provided with a case containing all or part of the electronic processing unit and equipped with a display system visualizing at least one indicator pointer having a time-variable orientation such that the angle formed between the indicator pointer and a first fixed reference axis of the dial is equal, at all times, to the azimuth of the Sun established by the processing unit, and a time graduation calculated by the electronic processing unit and displayed on the periphery of the dial in the form of a plurality of time points positioned with respect to the first fixed reference axis as a function of the azimuth of the Sun respectively at the hours whose time points are representative, the indicator pointer thus indicating, at each instant, simultaneously: ∘ a representation of the relative directions of the Sun and of the cardinal point of the culmination of the Sun, the difference between these directions being equal to the value of the azimuth of the Sun at this instant and in this place, said representation being constituted by the angle formed between the indicator pointer and the first fixed reference axis of the dial, ∘ the current legal time of the place where the electronic timepiece device is located at this instant, by reading the time whose time point of the time graduation towards which the indicator pointer is pointing is representative. - an electronic processing unit provided with at least one processor configured so as to periodically: ∘ determine first geo-location parameters associated to the place where the electronic processing unit is located and second parameters concerning the current legal time legally associated to this place, ∘ and establish, according to the first and second determined parameters (11, 12), local horizontal coordinates of the Sun in this place from predetermined calculation rules stored in a memory of the electronic processing unit, the local horizontal coordinates comprising at least the azimuth of the Sun, ∘ determine first geo-location parameters associated to the place where the electronic processing unit is located and second parameters concerning the current legal time legally associated to this place, ∘ and establish, according to the first and second determined parameters (11, 12), local horizontal coordinates of the Sun in this place from predetermined calculation rules stored in a memory of the electronic processing unit, the local horizontal coordinates comprising at least the azimuth of the Sun, - a dial provided with a case containing all or part of the electronic processing unit and equipped with a display system visualizing at least one indicator pointer having a time-variable orientation such that the angle formed between the indicator pointer and a first fixed reference axis of the dial is equal, at all times, to the azimuth of the Sun established by the processing unit, and a time graduation calculated by the electronic processing unit and displayed on the periphery of the dial in the form of a plurality of time points positioned with respect to the first fixed reference axis as a function of the azimuth of the Sun respectively at the hours whose time points are representative, the indicator pointer thus indicating, at each instant, simultaneously: ∘ a representation of the relative directions of the Sun and of the cardinal point of the culmination of the Sun, the difference between these directions being equal to the value of the azimuth of the Sun at this instant and in this place, said representation being constituted by the angle formed between the indicator pointer and the first fixed reference axis of the dial, ∘ the current legal time of the place where the electronic timepiece device is located at this instant, by reading the time whose time point of the time graduation towards which the indicator pointer is pointing is representative. ∘ a representation of the relative directions of the Sun and of the cardinal point of the culmination of the Sun, the difference between these directions being equal to the value of the azimuth of the Sun at this instant and in this place, said representation being constituted by the angle formed between the indicator pointer and the first fixed reference axis of the dial, ∘ the current legal time of the place where the electronic timepiece device is located at this instant, by reading the time whose time point of the time graduation towards which the indicator pointer is pointing is representative.