Ar fore llonydd yn ystod gwyliau'r Pasg, roedd Rhys, Cerys, ac Owain yn cerdded drwy'r bryniau gwyrdd ar eu taith maes daearegol.

On a quiet morning during the Easter holidays, Rhys, Cerys, and Owain were walking through the green hills on their geology field trip.

Roedd yr haul yn gynnes, a'r cennin Pedr yn blodeuo.

The sun was warm, and the daffodils were in bloom.

Rhys, gyda'i lygaid yn disglair, roedd yn dynn i feddwl am ginio ei fam-gu, sef traddodiad bob Pasg.

Rhys, with his eyes bright, was keen to think about his grandmother's lunch, a tradition every Easter.

Yn sydyn, daeth Cerys ymlaen at drws metel mawr wedi'i guddio yn y glaswellt.

Suddenly, Cerys came upon a large metal door hidden in the grass.

"Beth yw hwn?

"What is this?"

" galwodd, wrth agor y drws.

she called, while opening the door.

Roedd Owain yn swatio, gan edrych am drychineb.

Owain crouched, looking for disaster.

"Dewch 'mlaen," cytunodd Rhys, gan geisio bod yn ddewr hyd yn oed os ofnai leoedd caeedig.

"Come on," agreed Rhys, trying to be brave even if he feared closed spaces.

Daethon nhw i mewn i'r bunkeri, un oedd yn pwerllu uchel o'r Rhyfel Oer.

They entered the bunker, which was a high-power structure from the Cold War.

Roedd y llawr yn llaith, ac roedd arogl hen nwy yn y lle.

The floor was damp, and there was a smell of old gas in the place.

"Wel, dyma rywbeth!

"Well, this is something!"

" chwarddodd Cerys, wrth archwilio'r coridorau dirgel.

laughed Cerys, while exploring the mysterious corridors.

Alltud o obaith am funud roedden nhw wrth i'r drws caeu'n glep y tu ôl iddynt.

They were momentarily exiled from hope when the door slammed shut behind them.

"Mae'n gul yma!

"It's narrow here!"

" gwaeddodd Owain, gan glynu wrth y wal.

shouted Owain, clinging to the wall.

Roedd Rhys yn gwybod bod angen cynnwrf oedd, ond roedd yn bryderus am ginio'r teulu.

Rhys knew excitement was needed, but he was anxious about the family lunch.

"Dewch 'mlaen, Cerys," galwodd Rhys, gan obeithio y byddai ei synnwyr o antur yn dod â ffordd allan.

"Come on, Cerys," called Rhys, hoping that his sense of adventure would find a way out.

Gan daflu ei flashlight o gwmpas, canfuwyd hen fap gan Cerys a ymddangosai ar y wal.

Throwing his flashlight around, Cerys found an old map that appeared on the wall.

"Mae'r map yma'n dangos ffordd allan," meddai Cerys, yn hoffi ei dioddef garwriaeth.

"This map shows a way out," said Cerys, enjoying his suffering adventure.

Ond cyn iddo gael cyfle i weld, aeth y goleuadau yn dywyll amfnau un eto.

But before they had a chance to look, the lights went dark again unexpectedly.

Telynais Rhys ei hun i anadlu'n araf, gan glywed swn rhyfedd yn adleisio trwy'r coridor.

Rhys reminded himself to breathe slowly, hearing a strange sound echoing through the corridor.

"Peidiwch â phoeni," at Bellodd Owain, "mae llonydd y Pasg gyda ni.

"Don't worry," Owain reassured, "the peace of Easter is with us."

"Gyda'i gilydd, canfuwyd drws canolog a oedd yn arwain at wych gohebiaeth arall, a chegog orau yn yr haul a thywod ar yr wyneb.

Together, they found a central door that led to another marvelous corridor, and they marveled at the sun and sand on the surface.

"Rwy'n falch ein bod ni wedi dod allan," meddai Rhys, wrth edrych ar ei wraidd y cbatau o wlith.

"I'm glad we got out," said Rhys, as he gazed at his shoes soaked with dew.

"Rydyn ni'n cael cymryd ar ein hunain anturiaethau.

"We get to take our own adventures."

"Yn nes ymlaen, roedd pawb yn caru'r trywydd tiroedd, wrth gofio am eu dihangfa dychrynllyd.

Later on, everyone cherished the journey through the lands, remembering their frightening escape.

Rhys wedi dysgu bod yn bleser am anturiaethau newydd, a mwynhau byw'r foment.

Rhys learned to take pleasure in new adventures and to enjoy living in the moment.

Gyda glamp ar fywyd, cyrhaeddodd Rhys dîner Pasg fel roedd ei fam-gu yn gweini wy pasg traddodiadol dros ei fwrdd.

With a zest for life, Rhys arrived at the Easter dinner as his grandmother served the traditional Easter egg over her table.

Roedd fel breuddwyd a ddaeth yn wir.

It was like a dream come true.